You don't have to make big decisions immediately. It might be that you need a bit of time to sit with the realisations you've just had (eg of how bad things are, how much better they can easily be, and how lonely you are) and let yourself process and come to terms with it.
There's a bit of grieving that goes on around leaving/ending a relationship even when you know it's the right thing. All those emotions take a bit of time. It's ok to give yourself that if you need it.
You can love the person he used to be, the relationship you once had, and the dreams you had for life with him, and still it be time to move on. You don't have to stay in a bad situation to keep the good memories - they come with you regardless.
Some of the exhaustion you are feeling is from living in this environment with him. Coming home to someone who ignores you, shows no interest in you, and is a source of negativity and unpleasantness leaving you all walking on eggshells will absolutely drain you. It's a soul destroying way to live.
That exhaustion lifts once you're free of it, but you have to be ready to push yourself to make the leap to act, keeping in mind the long term reason and benefit. If that is what you want to do.
It would be easy to minimise this as one day, a one off, but you've described a long term pattern here, including what happened after you gave birth and the fact that although he promised to change he clearly has only changed partially. Enough change to make you feel you couldn't justify leaving, but not enough for life to be how it should be for you. (It's possible it might not be, but that does indicate deliberate coercive control/abuse.)
It's draining and lonely for you to live like this. It will be really hurtful for your children to be living with a parent who makes them feel unlovable (whether or not he does so deliberately, whether or not he protests that he does love them - it's the actions that matter).
Would a few sessions of individual counselling for you to talk it through confidentially with someone neutral be something that might help you figure out what you want to do and how to go about it?