Update 6 years and 8 months after BD..
I needed advice or help, anything, concerning the present state me and my kids are in and I asked ex-husband if we could talk in person. I am considering moving away and the kids are in on it.
I won' t give you details but I will give you observations and stunning awakening he has brought up in our conversation.

His words: You are the parent they have always known cause I was working in the bush then as a cop away from home most of the time. You are all they have. They refuse to come live with me and I don' t blame them. I know why and I understand completely.
Your family are good to and for them unlike mine who I have tried to hide from them because of shame I have towards them. I am not a good example when it comes to drinking cause I drink a lot (he could not keep eye contact on this one. he looked sad and shameful). He agree on us moving out of this town (WOWWWW !!! every time this came up, a HUGE fight followed )
He is trying to convince us into moving closer to him. We do not want that. The kids said he would control our every moves and would get from one bad situation into another. I believe them. They have a lot more contact with him than me. In fact, my contact with him is less than 1/ month.

Well, if you have been with me since day one, you will see how HUGE this is. He doesn't blame us anymore. He listen and participates in solving problems with the kids and with me. He has been doing a lot of positive towards the kids like dropping in at work to say hi, buying grocery for our University daughter and spending the evening with her and her boyfriend. ( she said it was weird but at the same time, very nice smile ) All 4 children are getting the good side of ex- husband and I am so thankful and hopeful that it will continue.
that is it for now..