You've already decided what to do and I agree it's definitely the right way to go. Just adding my own comment.
If this person were a friend whom you really cared about, it might just be a case of chalking it up to her having a bad day or having had extra stress due to her mother's illness, etc. And of course, it would be forgivable. And a good friend might even realize that her remarks were a bit rude and apologize.
But this is someone you already don't like very much, for whom you did a favor, and apparently, that favor was not appreciated. Now, it might still be a case of having a bad day or stress, but because it's not someone you have affinity for, it's better to just ignore it and move on.
To me, this kind of thing is only worth addressing if the friendship is one which I want to maintain. If it's someone I don't care to be friends with, there's no point in causing myself any further irritation over it.
And yeah, lesson learned. Don't lend her anything else.