I was like you 6 months ago. It will get better.
Stop trying to understand what he wants and why he have done this and start thinking where you are and what you have to do to move forward.
He doesn't care about what you want or how you feel do the same. He has done it and that is a fact.
Don't let him play mind tricks. Stay strong and focus.
The turmoil will pass. One step at the time and one day after another.
Speak to family and friends or here if you need to vent. (This applies to all the process).
Reassurance: tell yourself and the kind that everything is going to be fine.
Setting a new ground:
Look your economical situation and any possible economic help you can have (they are there for this kind of situations).
Claim him the child maintenance.
Once you work out your moneys in and and out. Either change the tenancy to your own, look for other place and in the meantime put yourself in the council housing list.
Look everything, how long do you have left in the tenancy, is affordable? If so try ato change the contract if not stay there until you find an affordable better place.
He is not going to evict you or the kids he will have to continue paying the rent. He is not going to die if he pays two or three more months of rent does he?
Look if you can do some paid work.
All of the above one think at the time. In a few months everything will be in its place. And you will be FREE of his shirt
All the strength for you