How to deal with unemployed, depressed, alcoholic roommate that still pays rent and keeps things clean
Background context: I (28F) have been friends and roommates with my roommate (28F) since college. We've lived together for about 8 years, even moving to different cities together.
Our lives have gone in very different directions. I finished college, built a career, and have been with my boyfriend for 4 years. She dropped out of college, worked an entry-level job until she was fired last year, and has been unemployed ever since. Her parents pay her rent, she doesn't have friends besides me, drinks heavily every day (usually 1/3 bottle of vodka or 6+ seltzers), and spends most of her time at home scrolling on her phone. She isn't disruptive or a terrible roommate. She mostly keeps to herself and cleans up after herself but she doesn't seem interested in changing her situation.
I've spent years trying to help her figure out what she's struggling with, but I've realized nothing changes unless she wants it to. Living with someone who spends every day drinking and doing nothing has made the atmosphere in our home feel really depressing, even though she isn't causing any obvious problems.
Our friendship has changed over time too. She gets visibly upset when I spend time with my boyfriend or other friends without her, but when we do things together it's hard to connect because she has nothing going on in her life anymore. I don't want every conversation to become about her struggles, but I also don't know what else to talk about.
The biggest issue is that my boyfriend and I are ready to move in together. When I brought the idea up, my roommate said she'd rather kill herself than live alone. This isn't the first time she's made comments like that, and now I feel trapped. I feel like moving forward with my own life could put her at risk, even though I know her life is her responsibility.
I've talked to her parents multiple times, but they mostly say they hope she'll eventually snap out of it. I know we've all enabled her in different ways, but I genuinely don't know what else to do. I care about her and don't want to abandon her, but I also feel like I've put my own life on hold because I'm afraid of what might happen if I finally move on.
I feel responsible for someone who refuses to help herself, and I don't know where the line is between being a good friend and sacrificing my own future. I'm not sure where to go from here.