Added: Now that you have added that she is a teen, I'm going to change my advice. I wouldn't be too quick to think now that she is talking about you on FB. Teens bring up all kinds of stuff on FB, and it very well may NOT be about you.
I'd text her to call you on the phone for a chat - tell her you two haven't talked in a while.
Is she still in school? If she is, then she has wants instead of needs. That's far different than if she is no longer a student and trying to find a real job. As far as no car is concerned, that something she has to earn money toward. Catching rides with friends or neighbors, even if it's two hours early for her shift, is what she has to look for. Or someone dropping her off at the bus stop. There is also cab fare that can come out of her paycheck (cheaper than owning a car, btw, by far!)
These are things that probably haven't occurred to her because she has never HAD to do them before. Perhaps the best thing you could do is make her aware of her options and how to find the resources she needs in order to succeed.
When my kids were in daycare, one of the daycare workers I really liked was having a very hard time. I asked what was wrong, and the director shared with me that her mom had died and all the bill collectors, including the hospital, the landlord and the utilities were calling her nonstop at the daycare. She was trying to pay them little amounts every month out of her daycare wages, but it was all so overwhelming for her. This director AND this young woman had no idea that she was not liable for her mother's bills. I called legal aid, got a phone number and name for her, and went to her with the info for her to call. Legal aid wrote letters for her, and the harassment stopped, and she didn't have to pay another penny. I only wish I had known a lot earlier and I could have helped her then.
The only way to learn stuff like this is to either read a lot, or live life in a way that you have to figure stuff out, rather than have everything done for you or handed to you. That's what you should do for her - lead her to water. But don't pour the water down her throat (ie don't give her money.)
Original:
I think that she is probably old enough for you to call her on it, Cupcake. Tell her that you were disappointed to see her remarks on FB about you. Tell her that it also pains you that she doesn't seem to want anything to do with you unless you help her out in some way.
See what she says. You will know that this is all you are good for if she gets defensive and bawls you out. If she says she is sorry and that she wasn't talking about you and that she truly wasn't asking for money, and that's not why she contacted you, THEN you know that she is trying to grow up.
There are posers and users in this world. I had ONE person pose as a friend and use my family - ONE. Never again.
I know you are struggling. Just be glad you have known this and weren't caught unawares. And you are right that if you continue to "help out" like this, you are enabling and that's wrong on many levels.
Good luck,
Dawn