So, it sounds to me like a natural thing for someone to hold another at arms length if they liked someone, and that person said "let's just be friends." So my guess is, yes, thats what he's doing. Moving on. You could always ask him, and then find your answer, though.

It sounds like you doubt yourself a LOT. I can relate. But if someone wasn't supportive of you and your anxiety, that to me sounds like you made the right decision about him and breaking it off. It might benefit you to talk about this in therapy, too (if you're in therapy).

One more thing is that I wonder if you have not enough to do. Do you feel busy enough? It sounds like you are dwelling on this.

It is my opinion that there are many people for us. (aka, there's many people out there who are a good fit for us!) Also, if it's meant to be, it will be.

I say, go ahead and ask him, if it will ease your mind. Who knows why he was unable to look at your message. It makes sense to me that he'd pull away. But who knows. Do you have other friends? I suggest you distract yourself with them and do some things you enjoy to take your mind off him and the anxiety you feel around it.