He gave me an STD...dump him?

My bf said he went out with his friend got pissy drunk & passed out in a van on the way back to their hotel & woke up bc a girl had pulled his penis out and started suckin it & he stopped her. Now he's gone to the dr bc his penis has a discharge & I found out he's got chlymadia...do I dump him bc right now I'm just confused angry & all of the above!! We've been dating for 5yrs never had an STD b4.