My children are 12 and 14. I did/ do ask them for help and they do nothing.
He has made it clear if we separated children would be with him. He will not budge so what choice do I have
You have plenty of choice. First of all, you don't let your children get away with doing nothing. If they don't help you, things don't get done and they go without.
Secondly, your husband doesn't just get to decide who has the children if you separate. If custody is disputed, the family court will decide. You don't have to just accept what your husband tells you.
It is plainly obvious from everything that you've said (the stuff about being noisy making coffee and then saying it was in the wrong mug, too) that he is a nasty, controlling bully. This isn't a husband being a bit of a twat. This is abusive.
Currently, your sons who refuse to help when you ask them to are basically learning their behaviour from your husband and they will behave to their partners in the way that your husband does to you. Please try to break this cycle.
You don't have to accept what your husband tells you, whether it's about the mug he has his coffee in or where your children live if you split up. You don't have to accept your children's refusal to do as they're told. It's time to consider your position seriously or nothing will ever change.