I felt compelled to create an account and post here. It's rare. I'd be grateful for just any external perspective and input.

Top line:
I'm in an uncertain relationship that's impacting me. I feel very down and very insecure. I'm considering whether to end the relationship and am looking for the right questions to ask to make that decision.

Background:
About a year ago, I got back in touch with an acquaintance. When we first met (two years prior), we were both seeing someone and while there was some flirting, we never took it anywhere.

This time, with changes in our personal circumstances we started spending time together (him initiating.) Three months in, he tried to kiss me and I resisted, but we continued to hang out. Five months in, he tried again and this time I let him. Our relationship became intimate. About a month after, he broke up with me saying he wasn't looking for a relationship and he didn't think I was ready for one either. (I had come out of a painful breakup and spoke often of that.) I accepted that and we continued hanging out as friends. Two months later, he kissed me one night saying he couldn't resist, and since then we're acting as though we're dating (three months.)

When we're together, he's very affectionate and we spend a lot of time cuddling and sharing new experiences and activities together. We have really stimulating conversation. When we're apart, I never hear from him. Since we're "on again", to spend time together, I do most of the outreach (which he always accepts.) We usually end up spending about 2 days a week together.

He tells me I'm his closest friend, and that he spends more time with me and trusts me more than anyone else. At the same time, he's a major cynic. He believes he's not capable of being in a committed relationship (he believes he's one of those people with limited vassopressin receptors) and usually gets bored within a year or two.

Being told that certainly doesn't make me feel great! Compared to his past relationships, we have a closer socio-economic background as well as more similar interests and careers. I've only been in stable relationships before lasting years and had always felt secure and valued in my prior relationships. Now I feel like I'm sitting on a ticking time bomb! I feel very attracted to him but I don't know if this rollercoaster is worth it!

Are all the signs I should end this? Or should we have a heart to heart talk, in which case what should I ask him? Ask if he's willing to work through things should we hit a roadblock? Ask how he feels about me? Should I ask if he's convinced this relationship has a finite shelf life, and if so, walk? We've fought twice, but were able to talk rationally through what happened and each time I believe we grew closer after the fight. But I mean he's pretty much said straight up he's incapable of committing.

Many thanks in advance for any thoughts you have to share.