How can I keep from gettin mad?

guys sometimes don't understand that it could hurt the girl, because sometimes we guys talk about our ex's not because we want to, but we want to explain something, like sometimes I have told my previous girlfriend about how things ended up really badly with my previous relationships and so forth, and I do not want to make the same mistakes etc.

simple. talk about your Ex. and if he gets mad, then tell him how do you think you feel when he does it? and if he keeps doing it, then play along until he gets annoyed and gives up. trust me will cave first. lol but do it right after he does it not hours later or maybe do both lol haha!

Understand that his ex is, and always will be, a part of his life. Yours are too! Don't take any of it personal (as hard as it may be sometimes), and you're not being constantly compared to her. If he didn't enjoy your company or find many endearing qualities he wouldn't be with you! Don't be discouraged at all or angry. Were you so inclined, I'm certain you could find context with your past relationships as well. When it happens, take a deep breath and realize it will pass. You're his focus and he's with *you*, so remember that.

Just tell him in a very caring and sensitive manner that it bothers you. I remember feeling the same way with a girl and she replied, "Well, I just want you to know everything about me." If he's a nice guy, he is not trying to turn you off or push you away. He probably likes you a lot and simply might want you to know everything about him so he feels he has no secrets or anything to hide. It does feel really weird to hear stuff about someone's ex, but if he's a good caring guy and not malicious he'll have a legit reason. Just ask him why he feels he needs to tell you things about his ex. And, make sure that you have a soft tone of voice so he doesn't feel like you are attacking him.

a guy that talks about his ex isn't always a bad thing. it could be his way of sharing more about his past and opening up more to you. try to take this as being helpful towards the relationship.