I was going to suggest setting up temp email account so we could exchange outside of the board here. We can think about that later if you wish.
You are a good man. It is great your concern for W and her being upset. BUT your feelings are valid too. Everything that lead to that moment was real. Her being upset could be justifiable but to me of much lesser importance in the big picture. Do not feel guilty. If anyone should feel guilty it is W for putting you in the situation IMO.
Have ye put in place a transparency plan. This is not about invading her privacy but demonstrating real commitment. I am happy you trust her explication but urge you to not fully believe everything until backed up by actions. Basic rule here!
I am glad you got that out in the open and W seems committed to your M. I bet you are relieved. I truly hope this is a turning point. .
R 25 years M 14 years S11 & S13 Working on it alone since Oct 2014 M in trouble a lot earlier (~2 years) Feb 2016. 1st R chat in a yr. Next R chat Aug'17 Still together