Missing him and not understanding(long)

I met this older guy about 2 years ago, I am 25 he is 45. When we first met, it was the best feeling ever, I don't know if anyone has ever had that feeling, kind of like honestly love at first sight. When the connection is immediately so strong, and you both feel like you're apart of each other. But that was how the feeling was, we instantly kicked it off, we could not stop smiling at each other and talking with each other. After meeting him that night, we kept in contact with one another, talking a lot, he is a divorced man with a little girl. & he was completely open and honest about his life from the start. Outside of texting, calling and face timing each other, we have maybe went out 3 times, and spent a few times just meeting up and having conversation, and it was honestly great. The first time we ever kissed it was amazing, it was the best feeling in the world. We have did almost everything except actually having sex. Our conversations have grew shorter and shorter and some days not even speaking at all. & it bothers me, I honestly don't think he is seeing anyone at all I do honestly believe he is busy with work and what not, but I also do believe people make time for what they want. The times we do talk we do talk sexual and say what we would love to do with each other, what we like and we even have phone sex. But I don't know why he stays away from me, and when I ask he says he doesn't want to get too attached and what not. & im starting to think he is really scared of me, and I'm wondering is it because im younger? Could he just have issues with other things? When we are around each other we can't keep our hands off each other and you can see how much we both truly like/want each other. There is nothing and no one that can deny how much we do like each other. It is completely noticeable. But why is it like he stays away? It hurts, I go out on other dates with guys and none of them compare him. He's so genuine, he doesn't pressure anything, he's so respectful etc.. I'm just lost and we have not talked in a week and I honestly miss him, I just don't know what to do..(please don't judge me)