How do I leave?

How do I leave a toxic relationship it's been 10 years of ups and downs mostly downs nothing's changed the whole time I want to do better with my life I no this isn't how it's supposed to be I left once but went back because I was young and had nobody else. For yrs I'd complain about him until I realised there's no point I no what I need to do and if I can't/won't leave I should just shut And and put up and that's what I've done I get envious when i read stories about how strong you ladies are to get up and go when you need to I know it's not easy but I'm feeling so low I live with him everything is in he's name he's mother enables him to be the way he is and controls all he's financial situations I know nothing will change I just want a good healthy independent life has anybody got any advice please?