relationship crisis over sexual dissatisfaction

[Blue]

You've set up a mentality of failure here, you expect him not to satisfy yo so, he can't and, that reinforces his belief in the same.

The first time (or two) that he penetrated me, although his pines was a little smaller than average I enjoyed myself very much.

That tells me his size is really not the issue. And if it was painful, how did he do it those few times? There is a lot of stuff going on here that, doesn't quite add up but, he did get circumcised so, that should have fixed the pain problem. You need to look at why you aren't satisfied with him now, and what's different from the first few times that you were good with him.

I think it's a mentality issue, but you'd know that and, maybe a therapist would help you both sort it all out.