Having a disability can be especially difficult on men's feelings of masculinity and desirability, because of society's ideals of men as strapping, physically powerful beings who can punch hard and lift heavy things. But there are some paths you each can walk that can help you meet in the middle. Likewise regarding your insight into your physical manner of showing affection, which may be causing him some discomfort.
Your perception that your boyfriend may suffer from a lack of confidence in his sexual appeal and dissociation from his body may be spot on. It sounds like you have an insightful and sensitive read on the situation already.
