My ex is a very sh!tty individual too. He just is. Always has been and always will be, but he is my daughter's father.
There are many shades of gray as AS states. What I do is not for everyone. I would never ever want to see or hear from the guy ever again if it wasn't for D.
So, yes, my ex is total sh!t. he has done sh!tty things. I've just managed to separate our relationship from us as parents to our D. Because I couldn't care anymore if he thinks he was right, wrong, justified, or anything. I just don't care. It's a long time until most get there.