I wish I had some advice to offer you, but all I can offer is that you aren't the only person worried about this. I haven't even had my surgery yet - I'm about a week away now. I'm more than ready, very excited to be where I am in my life, and generally feel a huge pick up in my self-esteem just knowing that there are huge changes coming for me. And yet, I'd be lying if I said I haven't had some rather strange emotional moments and fears, things that have never crossed my mind or worried me before, some pertaining to my libido and my desirability. I've spent years becoming the kind of person who could see herself as beautiful, desirable, sexually liberated despite being way outside society's "normal". I think few people would understand the things you or I are going through unless they were faced with this huge, monumental change, not just in our own perception, but in our literal image. In a lot of ways, it's like being given a new body. It's no wonder that we often have trouble understanding the very understandable confusion and fears that come with such a huge change in our self-image. Our bodies and our sexuality are at the core of who we are as people, and it's all topsy turvy during and after this change.
My only advice is to give yourself some time, and cut yourself as much slack as you can. You obviously love and are attracted to your husband, and he obviously loves and is attracted to you. Once your body balances out a bit and the surreal experience you are going through becomes a little less overwhelming, I bet everything will be just fine and back to normal. Maybe even better, who knows? Good luck!