Recovering alone after my husbands dementia diagnosis

HI Rick, I discovered my husbands affair 5 year in June of 2018. By Nov of 2019 he was diagnosed with FTD dementia. Before the diagnosis he was remorseful, we went to counseling and he got sober (he's an Alcoholic) Basically he was willing to do whatever it took to repair the damage he did. I feel we had just scratched the surface of recovery when he was diagnosed with his dementia. Now he does not have the cognitive ability to repair our marriage and I am now his caregiver and I am now emotionally alone in our marriage. Your information on your website has been a Godsend for me but I feel my situation is very unique. I would love to hear your thoughts.