Accusations

Accusations are rarely a positive thing. Accusing someone of something without being fully aware that it's the truth is very dangerous. Girls like to accuse guys of things regularly, and usually ti relates to other girls. "You were staring at that girl", "Did you hook up with someone else?!", "You're a dirty dog". It sounds crazy when you just read them here, but in the heat of an argument or the moments of lowest confidence, it's totally normal for girls to utter these phrases. I think if you keep accusing your BF (or a guy you just met) of things, he'll eventually just do them. First of all you're giving him no credit, and treating him like a monster by believing that he would do something dirty or low, either when you first meet him or later in the relationship when you should be trusting him. That's pretty hurtful when you think about it - especially if they haven't really done much to give you that idea. More importantly, if a guy has to listen to your accusations, defend his case, and convince you that he really does care about you, then he might as well just cheat or do whatever dirty deed you're worried about. He has to go through the crappy part of that anyway, so he might as well get some pleasure out of it. I'm not saying that makes it right, but I could definitely see a guy using that argument to convince himself to cross the line.
Just think twice before you accuse a guy of something.