have contacted womens aid in the past but they offer a refuge space too far away, my eldest would have to leave school.
I'm sure he'd rather change schools than see his mum with another broken tooth OP.
Is it really necessary? I guess I am asking is it that bad
Yes.
Your Dc are growing up witnessing their mother being abused, beaten up, cheated on & treated with total contempt.
It's a recipe for lifelong mental damage to them.
Don;t kid yourself they don;t see it. They do.
Sorry OP, I an NOT scolding you. But using very direct language, because you have been so ground down by this terrible bastard that you are not recognising how bad the situation is. 
Get yourself & the kids out.
It doesn't matter how far away the refuge is. what matters is getting you all safe, & being able to access the many services & support org's the refuge will signpost you to.
Everything else - living arrangements, location, schools, etc, can be decided later.
Can you email one of your friends, & borrow a phone?
Or contact Womens' Aid online?
TODAY?