I was fortunate my ex got a mistress half his age and lied about her for six years - it destroyed his credibility with my children and any one who sees him now with his girlfriend is going to play spot the idiot. As for my kids I try to be there for them. I try to be healthy and balanced and keep communication open. I always think the more people involved in their lives the better. I had a troubled Mom and right up to now, I just wished she was part of my life - kids always need their Mom.