Nobody deserves that. Dressing a certain way doesn't make you less of a human being. Beating someone for it does. Anybody whose close friend went through that would find themselves pretty affected. I would be more than shaken up, I'd probably need therapy for the rest of my life :S
Anyway, perhaps talking to a therapist would help you handle your feelings about this. Aside from that, talk to Adam and make sure he knows you're his friend and there for him.
I can't believe this stuff happens.