Yoou should probally talk to her about it nut be careful not to hurt her feelings. So put it in an "I don't believe that it is true but I'm just trying to make sure" kind of thing. Good Luck!
Why are you dating my girlfriend?
From his girlfriend Selena Gomez she is the one who had the STD first
dump her
yes
and also to add from the question above he has told you he does not really like his girlfriend
break up u hate her
Yes! You should tell her, you should also tell him how that made you feel. Think about it, you'd want to be told!!!!
You should tell him to get lost.
no, he does not. who ever told you he does is lying.
Lets face it if you are not maried then there is no real comitment in the relationship so it should not be too much of a problem other then an increaced risk of STD's.
No. Move on and find someone who is ready for an relationship.
Yes you should tell her that he is cheating. Because later, it will hurt her if not told.