What to do with a bad mother-daughter situation?

Let me start by saying this is my best friend. We'll say her name is Amanda. And we'll call her mother Kris. Amanda is an intelligent, well spoken, well traveled 21 year old. However, she has a hard time hanging on to jobs, or staying enrolled in college. She always starts something and quits not too long after. She said this is because she gets bad anxiety about her personal life and she lets it affect her professional and academic life. Her mother is chronically depressed. Many husbands, many divorces. She has two daughters. Both grown. Different fathers. Kris has extremely low self esteem. She has a bachelor's degree in journalism, but has never had a job title higher than substitute teacher. Every time Amanda does something brave or daring or adventurous, Kris brings her down. Amanda moved to Romania - three times. And every time, her mother would guilt her into coming home. Amanda moved out of her mom's house and got a really cool roommate. Her mom made her feel guilty for "leaving her" and persuaded her to move back home. Amanda tried moving to Texas where her dad lives. Her mom basically began a self destructive downward spiral until Amanda returned home. Every time Amanda starts a fulfilling job, her mom does something to sabotage her success. Kris will do whatever it is that she knows will bring Amanda down and depress her until she can't find the the excitement for work she once had. Her bosses notice this and begin to have a problem with her, which gives her more anxiety and she eventually has to quit. Amanda lives in a different city than me (my hometown). I want her to move to my city with me and start a new life. But she says her mom would be lost without her. I told her it's important to take care of your mom, but when she can't exist without bringing down her own children, it's not a good situation to be in. I told Amanda she needs to get her own life on track, without her mother, and then after Amanda's life is stable and secure, she can bring her mom back into it. I don't know if this was good advice to give. I'm so worried about her. I want her to succeed. She has so much potential, but I can't figure out how to get to her. Right now, her friend's mom has "adopted her." She has taken her under her wing. However this friend's mom is going through some personal troubles herself, and Amanda now feels guilty thinking about leaving her friend's mom. I think she has too much attachment to others. Oh, and also, they are also uninsured and have very unstable low income jobs. What should I do???