bugsy, just to add on to my last message now I have a little more time: I think your answer to your dh was exactly right. By suggesting counselling you are not closing the door on him but also not letting him into your life as before. He really has to prove himself.
One thing to ask yourself, if you have not done so already - how easy is it for your dh ot live alone right now. I mean in a practical sense. Has he enough money to rent a flat and enough knowledge to cook and clean for himself - or hire a cleaner/ live on takeaways. If the staying with a friend arangement is not working out for him, has your dh got the means to be independnent?
If he has, and he is still sayig he wants to move back in with you all then IMO there might be a glimmer of a chance he wants to give things another go.
If he is so happy with his girlfriend, why would he put that relationship in jeopardy by moving back in with you? He's already made the painful break after all. How does he think his girlfriend will not find out where he is living? You could tell her at any time.
From his point of view, moving back complicates things so his motives might not be all selfish. If you think 1. it is simply a money issue or 2. he is very mean and doesn't want to spend money on rent or 3. he hasn't the maturity to give a t* about anyone, including his girlfriend then think the worse.
If you feel there is more to it, then there could be a good reason for buildikng some bridges with him so as well as suggesting counselling, could you invite him round for family days, go out alone with him, etc whatever you feel ok with. Just give him a chance to prove his intentions and explain this is what it is. If he declines then you'll know where you stand and ther is definitly no reason to think about him moving back. And you'll never be worried that you did not give him this last chance. It may just be that the first novelty of his relationship has worn off by now. Byut that of course doesn;t mean you will ever accept him back with open arms.
Pre children I broke up with a live in boyfriend (now ex boyfriend but that's a different story). He started seing someone else. I was just getting along by myself when he said he wanted to come back. At the time (a confusing time) he was still seeing the other woman (but not for long). My friends were against me giving it a second chance, protecting me from further hurt. I was out on a limb when I agreed to give things another go. It took a lot of time and he had to prove over and over again that he loved me, but eventually we built up a strong relationship again.
I do not know what you should do and totally agree with the other messages that your dh has been horrible to you so there is little reason to trust him, but thought I'd put this viewpoint across to give you another angle on things.