You certainly have my prayers and my sympathy!
You are in a good position, though, to help the situation because you are suffering (both with the situation with your husband and your cancer).
Redemptive suffering is a forgotten subject in our modern world. Many souls could be saved through it. I would recommend you offer all your suffering in reparation for his sins and for his coversion. Always be patient, though. God has His timetable, we have ours. His is always followed to the “T” but He doesn’t publish ahead of time, unfortunately (or is that fortunately?).
Get others to offer their suffering for him, too. And their Masses. If I go to Mass today (I might at lunch, if work permits), I’ll offer mine for him.
God bless, and hang in there! God loves you and understands your suffering completely!