A "plate" is one of several women in your rotation. If you have one woman you're having sex with, there's nothing wrong with that, but she's not a "plate". Your behaviour towards her, and the overthinking and psychoanalysing underlying your post, reflects the fact that, to you, she's not a plate.

If you're wondering why you're this way, and the other guy is that way, you probably don't have to look much further than that. To him, she's probably one of several women in his rotation - a "plate" in the true meaning of the word. So he's got the abundance and lack of emotional investment to be The Skittles Man (look it up).

Like, can you imagine the other guy writing this long-ass post on the internet about this one particular woman? Of course not. Because she doesn't take up that much space in his mind. And that's the difference.

Basically, it's as simple as AF/BB. That's essentially what this all boils down to.

Ok. Some of this is going to hurt my man.

I've said the below in the interests of honesty and growth.

But you are half BP and half RP, and you've got some pain coming your way. I'm sorry for that, so maybe don't read all of this in one go.

We need more context.

• How long have you been seeing her?
• How often?
• Is she clear that you are fucking other women?

Apparently, she has been spinning another guy for years

Right. You say "for years", but how many years?

The interesting part is that he apparently gives her almost nothing in return. He doesn’t buy her things. He doesn’t take her out.

Right.

My read is that this guy is basically treating her as a convenient fuck toy while she continues hoping that eventually all the sexual investment she has made will somehow convert into a relationship.

Yes, but you are slightly misreading her side of things.

Although I regarded her as a plate, I actually did quite a lot of the stereotypically “beta” stuff. I bought her gifts, spent money on her, took her out, etc out of good faith.

What does "out of good faith" mean here?

TRP is clear on this stuff: provider behaviour kills sexual desire. It makes the whole thing transactional, and for women that overrides the sexual component. It also triggers "make him wait". It triggers Last Minute Resistance. It also makes her fake sexual interest: keep the stuff incoming in exchange for faux-sexual availability, thus masking her true sexual interest.

So seeing how willingly she has sexually invested herself in another guy who apparently gives her almost nothing in return has made me realise that, in a sense, I was probably paying for something that this other guy was getting for free.

You shouldn't be paying for women. The more you pay, the less you get. Women who want to fuck you will fuck you.

You probably have low self esteem, or are unable to fully sexually initiate, or you don't think you're that attractive. Thus you are compensating with dates, money, gifts, even though you claim to see her as a FWB (I can't use "plate" to describe women, women are not crockery).

Obviously that’s on me. I’m not complaining about having spent the money or gifts — I chose to do it. But psychologically, it has made me question what I was actually doing and what I was getting out of the arrangement.

You frame this transactionally. "I was paying X, I was getting Y". This means you were basically paying for sex.

PAYING FOR SEX DOES NOT WORK.

Paying will, at best, only buy you time with a woman (eg dates), but it doesn't buy you what you want: her sexual interest in you.

Success is attractive. The CAPABILITY of having spare resources that you COULD spend on her is attractive. But any actual provisioning or romance or expensive dates is provider behaviour. You should know this by now.

Better places to spend money: Yourself. Your clothes, your lifestyle. Invest in YOURSELF, not her. She gets to enjoy the ride, but you own the ride. There are ways to spend money to get sex, but none of it is on her.

There is perhaps one exception: a very occasional fun adventure-date.

For now, I’ve basically withdrawn my attention.

This is good. In a world where her sexual interest is waning, you should be downsizing the rest of the relationship to match (ie attention, time together).

Her recent messages are increasingly about her feelings, frustrations with life and how I’m supposedly her only friend, wanting to have dinner, etc. I’m not interested in becoming her emotional support system so I’ve stopped engaging.

Right. Tricky though, because she's done nothing wrong in her head. She has no direct control over her sexual feelings (any more than you do). She will feel and experience this as "entirely natural, and that's what I feel".

The challenge for you is to leverage this desire into hot monkey sex. It can be done, but you've got to do it right. Basically the trick, as far as I can tell, is to package it all up together: arrange a "date night" (or some other phrasing).... and tell her how fun it's going to be.... "Lavish each other with attention, I'll wear that shirt you like, you'll be wearing lingerie".

On the day: listen to her complain, be super understanding, for 15 mins max. After that "Ok, enough about our problems, tell me.... what's your favourite icecream?"..... or whatever. Have some convo ideas lined up in your head, and be relentless about changing the subject after she's unloaded.

What I’m genuinely curious about, though, is the other guy.

He has been doing what you should have been doing.

How does this usually end when a woman has invested this heavily into a guy sexually for years while hoping that the relationship will eventually materialise?

It usually ends with one of them getting bored/annoyed with the other.

At what point does she realise it isn’t happening?

Either she meets someone and goes monogamous, or he fails a shit test, or she starts banging-and-hoping someone else.

Does increasing the amount of sex, nudes, attention and availability actually reinforce the behaviour because she occasionally gets enough attention from him to keep the hope alive?

She hasn't thought it through this much. She's thinking "I want X, therefore send nudes".

Or does there eventually come a point where the accumulated frustration turns into resentment, confrontation, jealousy, or some kind of emotional explosion?

Depending on the woman, often yes. And that's fine, this guy is probably banging others, and knows the score. He'll shrug and walk away.

What puzzles me most is that she doesn’t seem to be walking away despite apparently getting very little from him beyond sexual attention.

But you're missing something here. You see it as "Pay sex, hope to get relationship". That's how women phrase it, but it contains a very serious lie in order to preserve her value.

Here is the reality: "Enjoy the hot sex, hope to get relationship"....... or, in some cases..... "Enjoy the hot sex, pretend to want relationship".

Why would she walk away? She's getting the hot sex she wants.

You need to understand this dynamic. She's not paying sex and hoping to get relationship. She's enjoying hot sex, and wanting to lock that down and convert to a relationship.

I’m also wondering whether I should be careful about anything on my end and how I should respond to her messages from time to time about having dinner etc. Given that I’m now pulling back while she is simultaneously becoming increasingly emotionally frustrated with this other guy,

Is she though? Or is it all upsides with him?

is there any possibility that I could end up becoming the fallback/attention source when things eventually implode with him?

I think you are that already.

And finally, putting the RP terminology aside for a moment, what should I actually learn from this situation?

Be him

I’m beginning to think I may have misunderstood the dynamics of the arrangement myself. I treated her as a plate,

You didn't treat her as a FWB though. You listen to her, give her attention, give her security, You pay for dates, you buy her gifts. You treated her as a girlfriend.

but perhaps I was behaving more like an LTR provider

Yes. Exactly.

while another guy was getting the raw sexual attraction without having to provide any of that.

Yes.... but getting what he has, isn't as easy as just withholding attention.

I don't know what you want, in general.

The "half girlfriend" thing can be done.... the FWB thing. More than sex, less than relationship, multiple at a time. It can be done. But you do need to understand the dynamic of what provisioning (gifts, dinner dates, listening to her, providing security) does to the female brain and how it acts as a turn off for her.

The standard questions: because they matter deeply: how old are you, what's your bodyfat percentage, how muscular are you.

And lastly, sorry for any pain this causes you.

In the end market forces always win in a LTR. Plate or not, it ran for a time because you provided enough benefit to her. You aren't providing what she wants so she withdraws (women withdraw anyway with time, being in love is short lived and a woman not in love is far more transactional that she likes to think).

You can't fool her forever. You can make a woman double down on her investment at first by playing her but in the end she is going to get pretty pissed off and resentful and realise you are not what she wants. She will feel stupid and that will make her more bitter and the hamster will turn it against you. You were supposed to be her guy, on her side, her support and you were a fraud. You will eventually just be another crappy ex. Men are such bastards!....

There is no magic moment the realisation comes but -unless there is a monkey branch- the break usually happens when you finally decide to stop putting in the energy to spin her wheels just enough to get her to give you just enough affection to keep you interested. You realise that you put in more than you get out and so you stop the spinning.

As for the other guy in your case, he was just higher value in her mind and he was just chill enough not to care enough to commit, so she kept trying. Another girl who valued you above the other guy would have done it the other way round. If she actually gets into a relationship with him, he will let her down and she will become bitter and walk. At the moment he is probably just high value in her mind, and while she had you she could hope. I expect that had she only had him, they would be done by now. She had a situation where you were the bread and he the butter in her sandwich. Take away the bread and you can't get far with the butter.