Re: Married people with kids - tell me
regular liar and unfaithful in the past.
I would suggest some serious marriage counseling. The professional kind, not the Life1 kind. And then to top it off, family intervention (his family, your family). Last resort should be divorce. I personally can't recommend anything, nor can anyone else here really, since we don't know the details.
Marriage counselors, if you find the right one, can be a gem.