Need some girly advice

Help! I think I'm in love with my old 'fling'.....but I have a boyfriend 😯 there's this guy I've been talking to for 4 years. We were never a thing exactly but we always end up hooking up randomly. Lately he and I have been talking wayy more than usual. Just talking. The problem is that I'm dating an amazing sweet guy... That I'm not in love with 🙁 I know this fling would probably never want to be serious and I feel awful for even thinking about anyone but my bf. Should I just cut all ties with both of them before everyone gets hurt?? (glad that's off my chest)