As a person who's done this in the past and am not proud of it, I can say honestly I support your decision 100%. How can I say this being a person that has been in your friends' shoes?
Because I know, that as I have during years after my ex left me with responsibility of two kids and finances, that I have had to learn the hard way some very real facts related to these things. She probably had always, like me, had a fall back, a cushion by way of other people that never hold her accountable. it took having to fully rely on myself, and most recently a huge crisis to fully realize how irresponsible I've been.
As a person that's a bad manager of money (only til now hopefully) I think the best thing you can do for people like her and I is hold us accountable and not enable the
responsibility irresponsibility anymore.
The only thing I can say to her credit and many people's that are this way is that there are many people who are afraid to hold others to standards trying to be nice and it makes it hard to learn how to manage money in a world where a quick way out is the standard for everyone.
*hugs* I hope you not helping her going forward will move her on down the road to better financial management in her life