
I would still recommend waiting until he’s single. Some people might see you in a certain light if you actively put yourself out there for him while he’s in a relationship- even an unhappy one. The last thing you want is for the girlfriend he has now to notice you doing this, paint you in an unflattering light, and then that change your friend’s opinion of you. Especially if the gf goes as far as to ask him not to hang out with you because of your actions.