What I would do.
Make a list of what the household income is, outgoings, and what he contributes financially to that.
Make another list of what the household tasks are - cooking, cleaning, childcare - and what he contributes to that.
Make a list of what the family emotional life is made up of - going places, making memories, eating together, helping with homework - and what he contributes to that.
Show him all the lists and say:
'You are a freeloader, in every sense. You contribute practically nothing to this family and this household. I and the children would be better off without you, and here's how:
and you show him your plan for how your life post-him will work:
less to do, as he is currently just adding extra work
no less money, as he contributes very little of his
and more planning capability, as you won't even be thinking about how to plan round him
possibly more money, as you will go to CSA (if appropriate)
and more time, because he will not be allowed comtact in your home and if he wants to see his children, he will have to take them out and have sole care of them.
Then make a fantasy list of what else you would do
- have more emotional energy to get a job
- find a new relationship with a real partner instead of a lazy bloodsucker.
Then you say - you have a choice.
If you want to stay here, you need to:
- contribute properly to household finances, permanently;
- contribute properly to the running of the house;
- be a proper part of the childrens' lives and a proper dad who cares for them practically;
- fucking grow up, eat with us, talk with us, be someone I want to be with and could even THINK of handing over half my savings to.
If you don't, you are out on your arse, because I've decided that you are not worth it anymore.
If you want to try, you change now, and we will review in six months.
I suggest you do try, because I think you too would be happier if you were to finally grow up;
but the way I feel now, if you decline my kind offer to allow you to stay, a little part of me will go 'yippee'
If that doesn't do the trick, nothing will
and you change the locks when he is next in work, take his stuff to his parents and say you'll be in contact about maintenance and childcare.