Hi mate, I hope youre okay. Im sorry you have been through this.
It seems to me that its a very typical case
Unfortunately no one wakes up one day and decides to be an addict. It creeps up on you and far too often, once good loving partners can turn into people you barely recognise who do things that you never would imagine they are capable of.
The thing is that in his active addiction he would have barely veen holding everything together, the lie he told the things he did, would have been hom trying to hold what little bit of normal life he had left together. That isnt to excuse his behaviour though.
What I find alot though is addicts and I was once the same, find it hard to accept any responsibility, because the truth is, if they was honest with themselves about all the things they have done they would probably find it impossible to look themselves in the mirror.
If you do want to find a way to buold back trust then he has to be willing to love by your rules and boundaries.
I would suggest, regular drug testing needing to be in place. If he has nothing to hide and wants to rebuild the relationship then he should have no problem with this.
Financial transparency is another thing. He should know that because of his actions you have every right to question Financial situations and again if he is real about making ammend he should respect that.
For so long it sounds like you lived on his terms and when you had enough and said no more the victim card was played. That doesnt get anyone anywhere.
Have a chat. Get everything out in the open. Set boundaries and make it clear that if he sticks to what he needs to do ie, being clean and contributing then you will stick to what you have offered, maybe thats staying a few nights a week. Having some time together like dating again and try to see if you can work through it.
For anyone battling addiction, having support is the number one thing you need however the people offering support can not be taken advantage of.
Be kind, be understand but be firm and always out yourself and children first.
I hope this helps in some way, feel free to reach out if you want to talk some more.
Stay strong
James x