What should I do?

Okay so I like this guy and he confessed his feelings for me about a week or two ago. We talk ALL the time and we often stay up late to talk about our feelings and how complicated our situation is. Not gonna get too much into it but there’s so much tension between us it’s crazy. The only thing is, he has a girlfriend which they’ve been dating for over a year. But he says he doesn’t know what he wants anymore since I came along. Idk what to do but just let myself fall for him and hopefully he’ll figure out what he wants ? Also, the situation is very very messy beyond that-(its a story for another time) but his girlfriend doesn’t know about me. What do I do?