The only thing stopping you is that you have nowhere to go. So you find somewhere to go. Ok, that's easier said than done, but you know what you have to do, so break it down into manageable chunks.
First of all, think about how you will finance a life away from him. CAn you get employment in any field? If so, however low paid, you will be ok as top-up benefits will take care of the shortfall. If you can't work, you will also qualify for benefits, which ok isn't ideal but it needn't be forever (and I'm pretty sure that if you can juggle an emotional vampire, a child and all the domestic stuff, you'll find being a single mother on benefits a doddle and will soon find yourself a job). If you don't know where to start with this, try this website or contact the CAB.
Having thought about that, the next step is to find somewhere to go. If need be, this can be a friend or family for a few weeks. Better would be a flat of your own choosing, even if that's far smaller and in a less-desirable area than normal - again, it's not forever, only while you find your feet. If that isn't an option because of finances, your local council have a statutory option to house you in an emergency situation, though be aware that this may be B&B initially. Or, you could ask your H to leave...
Good luck.