Unmotivated sister, can i help her?

Me 23f is worried about my sister 25f. She still lives at home with my parents and can never keep a job more then a year, she’ll find every reason to bitch and complain about her job and we offer to help her while she quits and finds a job she can handle and keep. But come round every time she will complain and find a reason to quit.

She’s entitled as in me and my parents let her smoke our bud for free, i know in some way we are enabling her.. especially my parents. She has no motivation to try and find a career or finish her GED. She was going to get her GED when her boyfriend broke up with her but then they got back together and she went back to the same attitude of “i don’t need that”. (btw her boyfriend is actually a really driven and somewhat successful person, all around great guy)

She has friends who have all moved out of state but really only has one friend here. She will non stop bitch and complain about this friend and how mad this friend makes her. I’ve even told her I don’t care to hear about this person anymore yet she doesn’t stop.

She’s honestly rude and ungreatful, can’t take any kind of criticism and like i said above she doesn’t want to work. She only cares about her boyfriend. Example: I recently moved and asked if she was free one day of the week to help me move, she said yes but the whole time she was complaining about how it needed to be quick because she has to be to her boyfriends cause it’s both their day off together. I asked a week in advance. I’m really trying to love her for who she is because i want her in my life but I jaut can’t stand her carelessness anymore.

She loves pointing out other people’s problems, including mine but can’t seem to acknowledge her own.