This is an interesting question.
In what way do you not feel comfortable with him? After all, he is your husband and you are having sex with him. Both of those facts seem to indicate a certain ‘comfort level’, and yet you say that you aren’t ‘comfortable’. I’m not dismissing what you say, not in the least, but it’s curious.
The part about having lack of confidence issues with one’s body is pretty normal, and I understand that for some reason this applies more to women than men (at least in the USA). And I have no idea why, because women generally look so damn much better than men, in my opinion. Not that I’m dismissing those issues as irrelevant or immaterial, either, but it seems to me that anyone with a ‘normal’ (i.e., not wholly conceited) outlook on life recognizes the imperfections of his or her own body, and perhaps magnifies that sometimes (and maybe does that ‘more often than normal’, even, which doesn’t make the feeling itself abnormal). So at a certain level you have to accept the reality of “it is what it is” and just ignore some of the ‘feelings’ you have about that.
I think one way that you might overcome some of that feeling is to open your eyes (put aside the discomfort that you might feel to see what can happen) and set out to deliberately seduce your husband next time you’re in bed – or next time you’d like to take him there. That is, gently but firmly and completely take control of the foreplay and watch his reaction as you touch him in the ways that he likes, and do ‘more of this’ and ‘less of that’ as you see what does and does not turn him on. Make it last. The longer you keep him aroused – and non-orgasmic – the longer you’ll have him in the palm of your hand. Maybe literally.
Most of the time (speaking for myself here) when I sense my partner’s excitement level rising, it has the exact same effect on me, whether or not she is ‘doing’ anything to me or not. And you can tell these things by touch and by sight even more ‘honestly’ than you can by what a person says. Bodies don’t lie too well; when you find his erogenous zones and slowly tease him with them by taking complete control of his reaction I think you may find your own confidence as a seductress increasing to the point where he may feel a bit intimidated by you.
Robert A. Heinlein said it better in fewer words: “A true lady takes off her dignity with her clothes and does her whorish best.”