Ok so my friend, who's a girl, likes this guy that I really don't get along with at all. Should I tell her things about him, or let things just happen on there own? Like should I try to kind of warn her about him, or just let her find out. Basically I know he's going to either cheat on her, or dump her for the next pretty girl that comes around. And I know this because he has a history of it, and he talks about how he has "sick wheels for hot chicks", but that he doesn't care at all about peoples feelings. Seriously.

Knife called lust

I think you voice your concerns in an honest way, and with facts, not just feelings, and then let her make her own choices. She is a friend, you have to support her when things are rough, whether she heedss your warning or not.

Its still her choice.

Thanks I know its her choice I was jist wondering whether I should warn her or not. Thanks for the advice

Your friend obviously knows that you don't like this guy,so is there a chance that if you tell her everything you know it might back fire.There is a possibility that she may turn on you saying that your only jealous etc etc.

On the other hand,if he does cheat on her and they break up,she might also say... "why didn't you tell me?"

It's a no win situation.

I think even if you did tell her,she might say.. ".he won't do it to me",truelly believing at that time that he won't,I hope he doesn't,it might be that they may find something special between them which will turn him around completey.

Probably your best friend has heard all the gossip about this guy already,but chooses to ignore it or make up her own mind.
I think I would let her do that,but watch out for her at the same time.

Yeah that's not really it, she has no idea what kind of person he is, another thing I forgot to mention just as an example was that one time at a party they made out, and too be honest, my friend is really really pretty, and the guy gloats about "makig out with my best friend" to everyone he knows. Meanwhile she doesn't even know the kinds of things he does.