Sister signed off work to party

Advice please - uk based
I’ll keep this short
Basically, my sister has been working for a few months.
She has been 18 a few months but she’s been going out and getting drunk Fridays, Saturdays and will ‘pop in’ to a club and have a few drinks through the week (and drink drive)
2 weeks ago, she went out Friday, came home 5pm Saturday to get ready to go out again, and came home 5am Sunday. She slept most of the day, and then went out with her friends that evening (didn’t drink apparently).
She called in sick to work, claiming she’s been throwing up (not true).
Anyway that day she was off, she decided to go out again. She didn’t get drunk and was home mid afternoon. She decided she hates her job and wants to be free. She started bad mouthing her job and her co-workers. She literally refused to go to work the next day, and lied saying her mental health was bad as her dog was ill. She then got signed off work for a month. Under the impression that her mental health was bad. Everyday these last 2 weeks, she’s been going out with friends, partying, getting drunk. It pisses me off because she is completely fine. She just wants to get drunk.
She is actually a horrible person. I’ve always said she is a sociopath.
What can I do? Our house is trashed because she refuses to clean up after herself, she spends all day scrolling then goes out all night. But she’s happy because she gets free money without working.