Re: commitment phobic? a bit long
I don't think you necessarily have a problem, I think you're just a typical guy who hasn't found the right woman yet. From what you've described here, it doesn't sound like you were ever really in love with either of these girls. But you do seem rather self aware and willing to learn and grow from your mistakes and experiences, and that's always a good thing.
Mostly, I'm really glad that you see now that "I didn't want to hurt her so I saw her and slept with her even though I really didn't want to" is rather a lame excuse. You hurt a woman much more and cause her much more pain by leading her on, sleeping with her and making her think you care when you don't than you do just being honest with her and telling her it's over. That's an important step.
I think it just takes time, experience, and meeting the right one. When you find the right one, you won't feel trapped or obligated. It will feel right and fun and wonderful.