Interesting question, because I think we all have, or will have, this scenario at one time or another.
My wife has a friend who we help out a lot. She's a single mother of 2 young kids, she can't hold a job for more than a month, and she constantly makes choices that keep her in her situation but she's always asking for help. My wife has had to tell her straight up, "I'll help you if you are doing something to help yourself." Basically, "meet me halfway", or "I'll put in as much effort as you."
Most of the time this is the case and I like to believe it will make a person become independent over time, but this friend is constantly on this roller coaster of life. Things will be going good for a bit, then she makes some bad choices, often the same ones as before, then things head downhill.
It's tough to see her struggle and my heart, and my wife's heart, want to help her as best we can, but if/when we bend over too far to help, it just enables her to stay stuck in her situation.