Ex-gf's new boyfriend who is also ur friend is a jerk to you now, why?

anyways so my gf was being pretty slutty and at the same time ignoring me so i broke up. now i completely ignore her, now she is dating my (overweight and ugly) friend, who i always used to joke around with. and now i cant because he gets all pissy when i push him or something. then randomly he goes and tells me "hey man i adnt really noticed but u got some bad acne, u should use proactiv, i tried it and it worked" wtf? and hes all pointing at it "look you have some here and here, and mostly here" am i going to have to ignore him too?