I am really reluctant to say anything that suggests I am trying to control his relationship with the kids. I struggle with this as it seems to me he is often causing them more pain... but he really goes off if he thinks i am stopping his access in any way.
The kids are old enough, I think, to make their own decisions about seeing him. I can't really stop them or make them.
And i do believe he has to face the consequences of what he has done in regards to them. He has created this relationship with them.