My DH is a grumpy git quite often, feels quite ok with dumping his anger over anything on me, doesn't do this with his friends or work colleagues, just me. And I have been getting more pissed off with it but that is not really why I am responding but I am interested in the responses.
My father was a miserable, grumpy alcoholic, drunk once or twice a week but over 50 years that is more than enough. So my Mum put up with this. I can remember thinking through what would have happened if she had left him (which I, naturally, thought she should have at the time).
There would have been the guilt and worry about leaving him on his own (couldn't even make a cup or tea), then moving to a new area near my mother's family, new school, and as my mum was a sociable type, eventually a new man in her life (not good from my view as a teenager), and I came to the conclusion that probably it might have been teh right decision for her to stay with him, from my pov not hers.
So - difficult for the OP. But I would say, and I am trying to do this myself in my own marriage which is good when he isn't being angry (DCs left home and comfortably off), that OP needs to form her own life not including DH. Hobbies, interests, new job, new qualifications. Perhaps get help in the house so you can go out and away from him more, work longer or whatever. So DH's behaviour is a minor irritation, not a depressing weight on your enjoyment of life. (this is sort of what my mother did, had interests and friends outside the home).
Apart from that I would suggest talking to DCs, not to condemn DH but to explain that you are finding DH difficult (They MUST have noticed this) and explain that you are trying to find more things to do outside the home to get a break (or whatever you say to explain things to them). I say this because nothing was EVER discussed when I was young, and your imagination makes things worse and the fact that you are never given the opportunity to express your anger or anxiety over what is obviously an unhappy situation is bad for you, your DCs might benefit from a chance to open up, I know I would have.