Oh OP, that is very hard on you and the children.
For your children to verbalise that they don't think he likes them indicates that he has really damaged them already.
I cannot overstate that.
No matter what his good points are, that is so dreadful, so wrong, so permanently damaging ......that it cannot go on.
You need to look into how you will separate, how it will work housing wising, financially etc.
Then sit down with him and present it as a done deal.
He really needs to know that such is the emotional abuse that the children are suffering at his behaviour, that it really is better he leaves.
Do you want your children to have serious emotional problems in the future?
Because it is highly likely.
Of course parents can be stressed and cranky, they are human.
But for them to ask why he is horrible and for them to verbalise that they think their own father doesn't like them, means that enormous damage is being done to them every single day.
I can only imagine how hard this is for you, but they need you to protect them from him, desperately.
Emotional abuse like this destroys lives.
It gives children anxiety, depression, CPTSD, which is not something a person can usually recover from, likely just coping skills to help them limp through life.
You sound like a loving mother.
Reach out for support from Women's aid, and your GP, family and friends.
This cannot continue.
Your children can no longer be his emotional punching bag.