This is beyond the pale and I'm sorry that you are on the receiving end of this. I, too, would move on from this person.
However, I'm curious. Noting the bolded:
Thanks for all the kind words! I am overweight but work very hard to wear appropriate clothing and carry myself in a good way. I was shocked because I considered her a good friend and she had never said anything to me in a hurtful way before. However thinking about it-I wouldn't put it past her. It sucks it has to end this way though.In the moment
the conversation occurred (or shortly after) I think a reasonable response would've been along the lines of 'What did you just say?', 'What did you mean by that?', and/or 'Do you honestly not realize how incredibly hurtful that is?'. Not everyone's brains work so well when stunned, though.
You mentioned her behavior was shocking, but upon reflection, you wouldn't put it past her. So, in retrospect, you noticed previously that she was not a terribly kind person, at least to other people at some point.
After a sufficient period of time nursing hurt (and I would be hurt) please look to the positive that she helped you not waste any more time and energy fostering a friendship with her. She has set you free to put your energies and feelings into more useful directions and persons.