Jaffaz- im a single mummy My XP left me i think nearly 3 months ago, due to "partying" commitments, whilst it is extremly hard as far as finances go she wil be able to do it im not by any means saying it will be easy because its simply not but you just make do. I work 6 days a week unfortunatly but that is simply because the bills need to be paid.
I would suggest she call up C/L and see what they can offer her as far as money goes.
During the breakup i thought exactly the same thing your friend is thinking but i bit the bullet and left him and havent looked back since.
I pay a morgage and all my bills myself the only thing i get help with is babysitting whilst at work.
but staying with my XP was alot more stressful then stressing about paying bills

if you have any other questions feel free to ask!
Hope this helped a little.