I meant to say, I'm sorry you're going through this. It's shit. I had about 4mths of torture, of him saying "I'm going to get a flat near work, and I may come and see you at the weekend, but don't expect it" 
I basically became immensely practical. I planned for a life without him - and it was going to be a good life, I can tell you! I told him we'd sell the house, and he'd have to pay maintenance for dc. I told him I planned to get a job, and I was planning to rent a flat in - it was going to be fab - it was going to be v bohemian and I was going to be a fab (and very skinny- thanks to divorce weightloss) single mum. I planned sports and hobbies I would take up. I made vegetable soup and drank
with friends and family. I threw myself into caring for my dc, and planning a life for us.
I basically refused to be downtrodden, or upset, or the 'abandoned' woman (I was, I was heartbroken - but I didn't let him see that!) I told him that there was no way I was going to be with someone who no longer loved me, that I didn't believe in staying together for the sake of the children. I told him to go if he no longer loved me - it was the only thing to do.
I opened the door wide for him, and shooed him out. I genuinely think he was going through some sort of early midlife crisis, as he has never done anything like this since. I think it was a reaction to parenthood tbh.
Take a deep breath, and tell him go. Help him leave. Calmly. Make practical financial arrangements for a new life for just you and the dc- child maintenance, benefits you;re entitled to, future job plans etc. Be fabulous. Don't do the 'pick me dance' (that's the worse thing to do) - just be your own fabulous self and tell him to bugger off. You have better things to do than weep over him. You're planing a life with your wonderful dc.
If he does come crawling back - it's a negotiation process. You will not go back to the way things were. You would be doing him a favour accepting him back. Be very, very reticent about taking him back. I told my dh all about the wonderful life I'd been planning with dc - you have to mean it though.
Be strong, be yourself. You can do it on your own. I would finish by saying that after doing all that, you may not want him back - he might genuinely be a wanker. He might not come back - in which case, you don't really want him anyway, do you? Because you're fabulous, and he's a loser. In which case you're well rid, and you've sorted your life out too.