Well, a lot of people in your age group have experienced some kind of marriage problem that often has included one or even both partners cheating. I was reading about the percentage of this happening being rather high these days.

Some marriages can be repaired even though this has happened and some don't.

It's not surprising that your wife has friends that have experienced marriage issues. And yes, she ended up with someone that cheated in his marriage too. Yes, I think your wife got swept away, and I have a suspicion the alcohol is a part of that too.

So let's see what your therapist has to say.