sometimes we are slow to learn and still want to be civil...it ain't gonna work in his case.
you have joint assets, a home and a mortgage, child care and responsibilities. you took a new job that affords you better control over your YOUNG CHILDREN's schedule. He's going to have to fork over more $$ for support and his parents are going to support THEIR CHILD and not make your life easier. expect them to throw as many obstacles in your path as they can.
I hope you get the support straightened out in writing that shows your drop in income and the cost of daycare for your kids...then it will be decided how much he has to pay. You don't care where the $$ comes from as long as the kids needs are tended to. If his mama gives him the $$, he'll just drink/smoke more.
sooner or later it WILL catch up with him and he will not be charming BS Artist that he preceives himself to be now. just sit back and take care of you, the stress can make you feel constantly sick...especially since your mother isn't acting in your best interest either...
hopefully his weekend will be so full of selfish plans he won't be circling you like a turkey buzzard.