How to love someone from an emotionally abusive background?

I have a question. I have a dear friend whom I’ve been involved with off and on for three years. We met 3 years ago when we both were about to graduate from college, and became serious (literally months before graduation). We ended because we weren’t in the same area, as I was going to move across the country. But we lightly remained friends. I was his last serious gf and he was my last serious boyfriend and that was years ago.

We’ve recently reconnected more, and a friendship is there. He comes from a very abusive background. His parents told him growing up that he would never amount to anything, and that he was worthless and a pieces of (s***). They also never told him they loved him. He has put himself through college and is a successful engineer. And while I know he is feeling better because he is successful, he still has all that crap to deal with. I have recently begun to tell him that I love him and it makes him very iffy. I’ve said it through text, but I recently said it on the phone and he seemed surprised. Like he was sure that I didn’t really love him. I know he still has a lot of issues and he struggles with them, but I don’t question when someone loves me (or I don’t question what I have to offer…other than material objects…he seems to think he has things to offer but only because he now has a good job). Should I continue to say it? He has said to me in the past that he’s scared of getting attached to someone, letting them in, and then them leaving him (he had this happen to him with his first love…they broke up over 5 years ago and she found someone else). I really love him, and only him but I’m not ready for a commitment. He doesn’t want a gf, and isn’t dating anyone. He has suggested I stay single to deal with things. I want to love him and be able to live my life, and find myself. And he also wants to be able to not have anyone be a factor in him moving or picking up and leaving (he’s looking at jobs elsewhere in the country). Will he interpret my lack of commitment as me not loving him? I guess I just don’t understand why can’t there be a happy medium where he knows I love him, and life happens. Basically I don’t know how to understand the situation, or why there is a situation.