He has said he’ll give me time but ultimately wants us to get married and all be a family.
That’s great. Tell him that when he’s in a position to offer you and your DS a lovely, clean and calm, rent free home, where he - not you carries the mental load, then you might feel in a much better position, as equals, to consider it.
I know you know it’s over OP, -now that you’ve seen him for what he truly is.
It’s impossible to unsee the flaws.
But please realise you are actually doing him a favour if only he would get off his lazy backside. He’s still young, he can now start to use his good judgement to make plans for the financial stability of his three children.
He was far too over-reliant on you and far too cavalier with your money!
He must have felt your resentment but was far too lazy to do anything about it.
Now he’s got no choice. If he wants to do right by his children he will have to start working at making his own sensible plans instead of using you.
All the same, it’s still sad for you right now as you grieve the loss of the man you fell for.
Good luck!
Relish the peace and freedom, - you and your boy both deserve it.