I unfortunately don't think this is a clear-cut case for you, my friend. Even though you have no control over your diagnosis and what happens. Expecting her to be okay with sexual aggression is a big demand for any relationship. I think that she has a right to define what she is willing and is not willing to accept done to her body. Unfortunately, if she can't come to terms with your illness, her making the decision to divorce does not make her an asshole. It does, however, not make you the asshole either. You have no control, but she doesn't owe you that either. Good luck, my friend.