Interesting to see, that regardless of what the denomination is, any church can still feel obligated to stick their nose in, and judge how people run their private lives.....
So, lets be a devils' advocate here :
Basically, I am trying to figure out, what business is it of yours between these two people ?
So.... the guy likes sex. A lot. That is not a crime. I know very little about pagan, (on purpose) but it would seem to me, that everyone has their own 'journey' in life. On that, most of us would agree.
If he wants to build relationships better with the churches help, then he is looking for guidance, not for judgement, scolding, and parenting. Did he sign on, to have friendship withdrawn, the minute you don`t agree ?
The woman involved, ...unless this 'spiritual' group, is going to pick up their pitch-forks and go inform the husband, it really has no right judging how they(church) were kept in the dark, until after the fact. If you want to advise, encourage, and counsel her to talk to her husband, then that is support of a spiritual kind. If you want to again, lie in judgement and ostracize, that would not seem very kind to me.
Or, has he asked you to lie for him ? Has she ? If it were that, I think you would of mentioned being angry, and being asked to do such a thing.
'Friends' can and should, make their own mistakes in life. There is a difference between having a opinion, and being opinionated. You don`t have to encourage things you dont believe in, but you can still have a friendship. Still be supportive, and still have a opinion, without sticking your nose in business that isn't yours.