Sounds like you guys spend a considerable amount of time apart from each other due to your circumstances. Combine that with the additional emotion drain of taking care of a sick parent and I see ample reasons why your progress is slowed....but you already realize this, and have a plan to reunite under the same roof in the near future.
So I don't think anything is wrong with you.
While the pain and hurt all BS feel after the betrayal of an A is NOT unique, our journey through the experience differs greatly.
Be gentle on yourself. Try not to compare your journey through this with others. I don't see anything wrong with you.
What I DO see is a compassionate husband (taking care of his Mom, doing his part to help you heal) and a smart wife (congrats on your academic accomplishments!).
Keep the faith!