How do you divorce with no money?

[PlentyOfBiscuitsWithTea]

My sister wants to separate from her husband. After a messy few years with him being hugely irresponsible with money (he starts businesses gets into huge debt and they get awful credit then redoes the entire thing over again - he is like a gambler). He is also emotionally and physically abusive. She has given him warnings and now for her own mental health knows she needs to leave. They have three children from teen to infant school. She can't move out of their house because her credit is so bad. Neither can he (but he could move in with parents). She is frightened if she doesn't leave him he will end up losing them their house (they've been so close and bailed out by family).
My question is... how do you divorce when you have no money? How can she guarantee she can live in the house (she thinks he will agree to pay mortgage if she pays bills) until her kids are 18? And if he makes further bad financial decisions between them could they take her half of the house and enforce a sale if they are no longer married?
If it were me I would see a family solicitor for all the fine details but she can barely afford the bills at present and is working like a dog. (To give this context she never worked a day after graduating where she met him and had a life of driving around in luxury cars, etc. When she realised what was happening she went and qualified in something and is working hard to grow her own business).

Are you sure she's told you the whole story.

Because what I've just read seems to be implying that your sister and her husband have lots of debt and bad credit and want to get divorced (in name only and with the minimal amount of financial outlay) and put the house in her name so as not to lose it to their creditors.

If she's qualified and working like a dog how come she doesn't have any money.

She can’t guarantee that she’ll stay in the house unless she can demonstrate that she earns enough to do so and a mortgage lender will allow her the mortgage. It would be irresponsible to rely on her husband if he’s a gambler and builds up debts anyway

@notsuch I don't think she's lying, no. I think she's been complicit in his delusions for a long time, yes, and has finally woken up to the fact that if they carry on the way things are going he could quite possibly lose the house. This has been coming (she has given him warnings to get a salaried job and stop taking risks) for years. The straw has been broken because she found out he is planning to start a new venture and she gave him 6months to get a "proper" job.
You can work like a dog and still not have enough to pay a mortgage and bills single handedly, unfortunately. She qualified in beauty. It's not well paid or regular until you've built up a solid client base. She also works assisting with a friend's business which is a very physical job, but again, minimum wage.
I guess I'm asking to see if there any women who have been put in a very uneven financial situation in which they are reliant on a man and have been for a long time and want to get out. Maybe I'm wrong, but I assumed (sadly) this would be a common scenario.
All the money she earns currently is going toward paying for their house. She said she has £3 left at the end of the month.

When I was considering using a solicitor to divorce most offered payment terms; a sort of pay as you go service. You paid a deposit then agreed an amount per month payable until resolution. Maybe she should have some initial phone consultations with local solicitors to get a feel for what may be achievable.

I left my very wealthy ex-husband and unfortunately had no choice but to rent for years whilst he remained (and still does) in the five-bed family home. Our kids were just 3 and 6 at the time.

Still renting six years on as I got a crap settlement (he lied about his earnings and conveniently "loaned" his brother the majority of his business - Chartered Accountant).

Nowhere near in a position to buy still.

PS. I work ft and privately rent.

She may have to accept that losing the house is the price she'll pay to get rid of him. If she sees the house as optional, then other opportunities open up.

Selling the house may be the best option, even if it seems like the worst thing in the world at the moment. She could do with cutting all financial ties to him as soon as possible.
Most solicitors will do a free 30 minute consultation, so that might be the best thing to start with. It will give her an idea of what her options are.