SBJ, I can see why you had a sleepless night. You are concerned for his marriage. It does appear that your ex and him are spending a lot of time together.

Would you feel similar if he was spending time with a women that is not your ex? What about if your kids were not involved? I know you said it is only your business because your kids are involved, but how do you feel when just looking at it with just your friends involvement.

I am guessing you would still be concerned as his wife is in a treatment center for a couple of months and he is spending to much time with other company.

Perhaps approach it like that. What would you say to friend about his behaviour, about what he can control? Leave your ex out of the equation for the moment. Just look at what he is possible doing to his marriage.

If you are still concerned then speak with him as a friend / mentor.

You ex and kids being involved will complicate things. Be sure you are not reacting. You need to be sure of this, and will most likely need demonstrate this to friend to get him to listen.

As a friend and fellow church member he may be receptive to your concern for his wellbeing.

If he is receptive you have a lot of compassionate advice you can share.

If he is less than receptive, you are going to have to accept that.

You are good person SBJ. Whatever you decide I am sure will be from a place of compassion and concern.

Feelings are fleeting.
Be better, not bitter.
Love the person, forgive the sin.