Is it time for me to think of myself and let my ungrateful sister look after herself?

My Mum died very suddenly 3 years ago and it hit my sister and I hard, her worse than me, and she just kinda gave up just sleeping all day, drinking and vaping. She did the washing and some cooking, whilst I continued to work full time and pay for everything and support her too. She wasn't on benefits, we struggled to pay the bills and I later found out she'd beeb drinking 1 or 2 bottles of Scotch a week behind my back, while I'm struggling to pay bills, and then stole from me (like only a junkie would!) First it was loose change out of my big coke bottle, then my credit card (she actually watched me phone the Police to report my card had been cloned, and only admitted it when they were going to view cctv evidence), after promising she'd never steal again, she stole a gold half-sovereign out of my bag (that i was going to sell to pay bills, not spend on myself!) and sold it at a local antique shop, even tricking me into taking her there by saying she was going to the chemist next door. We've rowed 100 times and made up, she's promised me that she'll change, but then every other week she relapses and won't move off the sofa, she only goes shopping if I take her and last Friday fainted outside the co-op as she's not eating properly, I told her she had to speak to the Doctor on Monday, but she refused and said she's alright. She only bathes if I nag her to and looks dreadful. I've trier to make allowances as she came out of a marriage to a bully, but I now wonder if she behaved like this in marriage and is that why he appeared to bully her? I KNOW she still drinks whisky so I said, I can't stop you, but control it. She got alot of Backdated PIP and UC which is in my bavk as she doesn't have an account ( I Gave her money for a new drivers licence to open an account but it never arrived, probably spent that on booze too!) We live in the house inherited from.my Mum which we HAVE to seek as my mum mum took out a lifetime mortgage on it and the want their pound of flesh - vultures! We thought we'd sold last August but were just strung along for 6 months so we lost the house we were looking at. The idea is if we buy together our money will go further. The house is under offer again and we viewed a house last week but she said she felt dizzy and didn't look upstairs, we are viewing again tomorrow with the idea of making an offer, but I don't think she'll come to look. I've been out of work alot for last few months and living off her PIP (Tthough alot if it was owed to me as she paid nothing for about 18 months and I took out loans and credit cards to get us through) when the arguments start, she talks about HER money and forgets what she stole from.me. there was also £500 cash from.my mum's account that should've lasted us a while, she spent that in 2 weeks and she sold a gold charm bracelet of mums for £900 and I saw none of that, though she tried to imply she'd "filled the freezer".I ask her to do basic things like tidy the corner nearbthe sofa she sleeps on as she just accumulates empty water and coke bottles and throws litter or empty vape boxes into the corner - probably just to annoy me. I've asked her 4 times to put a wash on today and she's not done it and has been asleep since after tea time. Asked her 3 times to throw out her out of date half lasagne in the fridge, not done, I've just done it. She eats about half a ready meal every and old bathes when I nag. I do end up shouting and getting I'm her face abd she's described me as a vile gorilla that speaks to her like shit. I've just got a new job today, starting in a week or so which I think I'll love, after afew false starts, and want to rebuild my life. I don't want to feel.like a bad brother but others ha e said I should start thinking of myself and the signpost for carers I registered at said I'm entitled to live my own life and have to ask myself if I wsnt to have to deal with her the rest of my life. As crap as she felt after losing Mum I felt the same but i worked.