Ahh... you know, we grow up surrounded by romantic relationships, so we probably expect to fall in love a priori. While I do understand how you're feeling, it's hard to judge, maybe he truly doesn't live up to this logic?

This would give me feeling of people settling for me, which isn't really appealing, in my opinion. But, in the end, that's up to each person's expectations and how they deal with relationships. How long have you been together?

Also, you say that he's a lot more 'social' than you are. This can cause you great anxiety. Just out of curiosity, if the situation was the same but he was as outgoing as you would you feel less anxious?