Recover from this?

[monkeysee100]

I'm just getting so resentful and bitter

My DH has never been hugely ambitious (although did make a big deal of exams he was sitting when we got together. He stayed in an entry level job for the first 8-9 years of our relationship then had a leg up into another company into a better role but has been demoted. He has two unfinished professional courses ongoing and fobs off thinking about a career path.

He's not great with the kids. He gets hugely frustrated with the five year old and barely spends any time with the younger.

I will return to my job. I've had several promotions, take part in national projects and my organisation has the highest externally moderated grade possible.

I do the vast majority of the house work. Anything else done at home is half arsed and unfinished. If I say anything I'm nagging and picking a fight.

I'm fed up of promises and targets that never get fulfilled.

Is there any way back?

Have you tried talking to him? Explaining how you feel. If you've tried calm discussion, perhaps it's time to be blunt.
I can understand if he isn't into the competitive side of work, and some men do find small children frustrating, but leaving you to do all the housework is just plain lazy.
He is perfectly capable of hoovering, loading & unloading the dishwasher, cooking sausage & chips, and taking the bins out. He needs to do his share if he wants to keep you.
What does he like? Anything you can build on?

You don't sound well matched. And you sound resentful. I think that it's unlikely your DH will suddenly have a moment of realisation, so unless you are prepared to accept this status quo, I don't think you'll ever be very happy in this relationship.