Is it possible that I only like the chase?

My mom and a few boys have said this to me and I’d always brushed it off but now it’s been bothering me a bit and I sort of feel like a bad person.

I’m only 20 and I’ve never really felt like I was in love before. I have been in one relationship where I felt like I did like him a lot, but honestly it was never too deep on my end and I admit I was still looking elsewhere so it’s probably for the best that it ended. Another guy who I thought I really liked a lot, initially started as an 8 month long crush. Eventually he told me he felt the same way so that was our chance, but I ended up flaking on him and leaving for college. He got a girlfriend later on and I proceeded to be hung up on him for the next few years. When we talked on the phone after a year or so, he said that he felt like I was only interested when he wasn’t available and that as soon as we got together I was gonna up and leave him.

Now this was a guy I really did have feelings for…or at least, I think I did. But whenever we were supposed to hang out, I always got uncomfortable and never really let the relationship materialize. Now I feel kind of mad at myself, like I’ve been self sabotaging potentially really good relationships for no reason at all. Do you think that this is just because I’m young and haven’t found the one yet? I realized this about myself, that I have a tendency to stray a lot and I want to improve. I feel like an idiot because I feel like I lost my chance with him, as I didn’t confirm or deny what he said and we haven’t spoken in a month.