Should I tell his girlfriend he wants to cheat with me?

[goodmorning]

you are a spam.

[Wakeup]

I do see what you mean, and I do agree, except that I do think it would give him comeuppance. They've been together for years and I do think he loves her, but right now he's having it all and hurting others in the process, and that's just not fair.

Your sour grapes are showing again, OP.

What's really sad and selfish of YOU (never mind him, we all know what he is) is that you are doing this in some misguided attempt to hurt him when in reality, you won't hurt him at all. Nor will it make you feel vindicated.

You'll do what you will (which is mostly always the case) but whatever you do, don't lose sight of the lesson this was meant to teach you.

[basilandthyme]

I'm just throwing out there that if I was his partner, I'd undoubtedly shoot the messenger.

[confused_]

Ok, I know what you're saying, really I do. Buuut...

So what if I want to hurt him? Of course I do! ... It's not like I want to hurt him by hurting her as I know hurting her would hurt him (if that made sense? ) I think that her knowing would also benefit her in the long run. And it would also hurt him. Also, I don't care if she 'shoots the messenger'. I don't know this woman and really don't care about what she thinks about me. Of course I want him to get what he deserves, anybody would. That's why people talk about karma. But to me, 'karma' isn't going to magically hit him on its own. If he gets caught behaving badly (with help from me) and loses everything (her and me), then that's karma right there.

[Wakeup]

Ok, I know what you're saying, really I do. Buuut...

So what if I want to hurt him? Of course I do! ... It's not like I want to hurt him by hurting her as I know hurting her would hurt him (if that made sense? ) I think that her knowing would also benefit her in the long run. And it would also hurt him. Also, I don't care if she 'shoots the messenger'. I don't know this woman and really don't care about what she thinks about me. Of course I want him to get what he deserves, anybody would. That's why people talk about karma. But to me, 'karma' isn't going to magically hit him on its own. If he gets caught behaving badly (with help from me) and loses everything (her and me), then that's karma right there.

Well, this just proves that: For you, this is about selfishness and revenge. It's not about doing the right thing at all.

I really want to tell her, but I think it's for the wrong reasons.

Speaking about Karma. (since you appear to believe in such a thing) As I said earlier, telling her just to reap revenge on him will result in bad Karma for you. Your intent is what would determines what comes back to you. Do you seriously think your intent is pure? Its not, so neither will your karma be.
(its not like you have the opinion that "she deserves to know, nor is it like you're trying to protect her from him otherwise known as good intentions)

Next time, before you have sex with someone make sure they're not already paired up with someone else and you'd not have to worry about your karma or his. You are sitting at the banquet of the consequences of your actions and you want to punish him for what you did.

Just do what you're going to do and so be it.

[confused_]

No, I'm saying I don't believe in karma. I'm saying that nothing would happen on its own, and that when people say 'she will find out on her own sooner or later' or 'he will get what he deserves eventually' , it's a load of sh*t. In order for something to happen, I need to make it happen. I already know that I'm not doing it for the right reasons, I said that in my first post. But I still think that she would be better knowing now. Like I said earlier, he wanted to sleep with me without protection, what if he does that with someone who has an STD.
And I was right in thinking that he had no girlfriend. Everything he did told me he was single. I think they had actually broken up but are not back together. Look, I've always said that if you sleep with someone you've just met, you can't blame them for not wanting more after the sex, because for all they knew, you only wanted sex too. I still think this. But this case is different. This was a guy I met and didn't have sex right away. A guy who explicitly told me he wanted more than sex. A guy who lied. And he put a lot of effort into this lie, being in touch all day every day, asking about my family etc, telling me about the things he wanted us to do together. I really don't think that it would have made a difference if I would have waited. He would have carried on perusing this way me until we did what we did. And even if he did mean it then changed his mind, he's come back for sex at the same time as having a girlfriend! Hurting the girlfriend by cheating and hurting me, as he knows that I like him and remembers how he used to treat me.
I already know that if you want to make sure someone likes you, you should wait to have sex, I know this. It's what I've always done. On this occasions, it was a little quicker than usual, but I had my reasons. Obviously I'll be more cautious in future...

[Wakeup]

Like I said. Do what you're going to do and let us know how it goes and if you get any satisfaction out of it.

One other question though. Why'd you need the opinion of strangers before you did what you want to do?