We are all under stress at some time or other in our lives, do we all make everyone around us miserable and nervous, no.
Home is supposed to be a sanctuary, not a battleground. If it's work pressure at the bottom of this, tiredness, stress, whatever, you and the DCs are feeling it too. If he can leave those stresses behind as he walks through the door he can rest and recover. If he feels worn out or finding it difficult to cope, can he see his GP? If he lets go at work like he does in your four walls then he will lose employment.
It will affect the DCs, if not already - how can it not. They hear the noise, they soon pick up on the fact that Daddy coming home = tension, upset. Mummy not being listened to or respected.
Verbal abuse could escalate to physical abuse. You can't possibly feel safe at home with DP but is there anywhere you can go with DCs to ensure that you're not at risk?
Lay it on the line, tell him that you can't go on like this. His behaviour is unacceptable. You know he can't be happy, you wouldn't have been with him this long if you hadnt loved him, his life matters and you have tried to keep things going. But he's changed and now you have to put your DCs and yourself first since he doesn't seem to. If he isn't willing to go and speak to someone about his temper and perpetual anger then you can't see how you can continue being with him.