Okay the fact that he's married but giving you signals like he's interested is already a pretty bad sign. It kinda shows that he could possibly be a person who is easily swayed by women and you wouldn't want a guy like that. Because if you ended up together, who is to tell that he won't sway to another woman? So honestly I think that you should just try to keep things platonic with this guy. If you are falling for him, try to keep your distance and meet new guys.