Here is the key, as Charbon says:
In order to be taken seriously in any situation in life, we have to have a bottom line that others believe. We have to be prepared to follow through in the consequences we give people fair warning about. So you need to decide if you are prepared to hold out for what you want - and whether you have the courage to walk if you don't get what you need from this relationship.
You need to have a bottom line.
So, what do you want to happen and see as fair?
Tell him
Tell him if he isnt more fair and responsible, you will do the same to him
If he still insists on seeing you as an unpaid nanny, wake him at a decent time, hand him the kids, and walk out for the day.
It wont affect them badly, as it wont keep on happening, in my view. It will affect them far less to have a pissed off dad looking after them a few times than to have an unhappy and lonely mum longer term.
And he will see that you are serious.
You must keep this up until he agrees to play fair (in which case, you will).
If he want at all after this, then he isnt worth the candle, is he? But at least you will have tried.
ps please dont say that he cant be trusted with them- if that's true, then you definitely shouldnt be with him anyway.