I'm at a breaking point and need help

I've been arguing back and forth about my bf and his new found gal friend in class. I've told him I don't feel comfy with him around her much because she likes him, yet he still goes around her. He's a guy that doesn't necessarily likes to go out, at least that's what he tells me because I constantly ask lets go this or that off campus and he won't do it. Yet when he gets out of class with her he'll go off campus....I've nearly killed this boy telling him it hurts my feelings and he doesn't like me "turning" into the mad part of me instead of the happy part and had the audacity to say "we're done" like its my problem. 
Yes I understand that he wouldn't cheat or do anything crazy, yet it's gotten to point that I'm pissed that he will do things with her but not me. He even told her I don't like her/am cautious of her. 
But not too long ago he got up in the morning! He never gets up in the morning on a day we don't have class. I ask him "you have to go somewhere?" He says "yes, I do"
 I ask "where" he mumbled under his breathe and I ask again he then just slips out the door to shower. 
Ladies I kid you not, I don't know what to do or say right now. I don't know if I should go crazy if he is going somewhere with after I told him we should do something this Friday or not. 
I'm at a breaking point! I really don't want to say goodbye but if he honestly thinks this is okay then I don't if I can do this. Faithful or not this is iffy.