sometimes people change...it could have been triggered by the alcohol, or he could have become so puffed up and full of himself he felt he no longer had to exhibit "good behavior"....he had his *wife* and she would never leave....
I think you have answered your own questions....and I agree, cut yourself some slack.....the *husband* blindesided you.
as for a therapist? the best place to start is calling your insurance carrier...certain plans only cover certain services...they will give you a list of local psychologists or social workers with a degree and the fee is minimal (often your co-pay)....cheaper than a bottle of wine, I paid $15.00 for 2X a week for the first year. if one doesn't click with you, you can try another...the first visit is like a mutual interview.