justafriend306, you are too decent
I don't know what it is about ppl. like that, but it says so much more about them than you. Give yourself credit for being kind & trying to help.
I cannot imagine how you felt, but I suspect that you are NOT the first & won't be the last person, with whom they have that attitude. I don't know if its entitlement or what (??)

but moving forward, you should have NO expectations.
If ever this happens again - Tell her
"she's welcome" or make an excuse & stay away for a LONG time, so that they will get a sense of your VALUE. Or tell them that you realize that your efforts were inadequate not to their standards (to
make them take ownership for their 'bad') and that you are sure (based on this), that you may be able to help - wish them luck WITH LOVE, be nice & move on.
They will learn the hard way.
However, if you want to go
in the way of peace & not do anything, (& too many nice ppl. do), then as I said
have NO expectations to shield yourself from being hurt again.
Generally though, do try to save yourself for YOU & the ppl. who show YOU appreciation. We are all not without unlimited resources!! Some of us learn late after expending energy on the wrong ppl. & having none for ourselves when it gets critical ...
Feel better