Don't feel bad...you are completely normal! With everything that has gone on in your life, sex is the last thing popping into your mind, and rightly so.
Try speaking to your husband, in a neutral location, about some of your concerns. Let him understand that you WANT to take part, in every sense of the word, with what he has been asking you to do. Get him to understand that you are not doing any of this to please him, that you would like to do all of these things. But he needs to understand what is going on in your mind. The pain can be anatomical (did you tear or have an episiotomy during childbirth?), psychological, or something deep within you that is manifesting this way.
If your pain is from childbirth, go to your doctor and have things checked. There is usually some sort of nerve damage that can cause pain, but that is not always the answer. If it is not something physically wrong with your "girl parts", then maybe you might want to speak to a professional about the problem and see if you are able to work through some of the current issues. I'm not saying you need to seek out a sex counselor but with everything you have had happen as of late, talking to someone about those issues could very easily fix this one. If it doesn't, well, you are still talking to someone that could help quite a bit.
Hang in there, you've got a lot on your plate to deal with and sometimes the hubby has to take a back seat for your health and well being.