Thanks to all who replied, I appreciate the insight
I discovered why my husband was questioning our marriage, it is because he is having an admitted affair with a woman in his AA group. I have met her. She knows he’s married. He doesn’t seem to care that he’s married. I am shocked beyond belief. This is something that I thought he would have done when he was drinking, not when he was 19 months sober. To say I am devastated is an understatement.