You poor thing... I am so sorry to hear you are going through this.

It's hard to answer your question about your marriage without having known you both personally before and after the strokes. Do you have someone who DOES know you both personally that can tell you better (and with honesty) if this behavior is out of character for him or unexpected? Also have you talked to his doctor to see if he can change some of his meds that may be causing these mood changes?
In the end, there is no band-aid for this kind of pain, and I am here if you want to private message me just so you dont feel alone. In the meantime, you are not worthless, ugly or unlovable. You are a devoted wife and caregiver and you deserve to be treated with love and respect.
Hang in there.