Irish, this is really a saintly move for your girls. I've mentioned this elsewhere, but in my first meeting with my children's counselor she told me that even the children of convicted murderers pine for their parents and want a relationship with them. While ultimately it has to be their choice, I would hope you would urge them to go at least once.
My H's abandonment of my children has not been as extreme as yours, but while they tell me they don't like him and don't want to see him, they come back in a manner that tells me they were happy they went. While they don't want to do it often, it seems to bring them some sort of peace to see him for themselves.
