I second this!
Please do not let this assholian "friend" come lounge around your house and clean out your fridge after the way she treated you. Geez, what a douchtard! I also agree with IZ, a bigger rift is exactly what is needed IF fences are going to be mended. Or else she'll keep treating you as a second class, hopeless case citizen.

She needs to know her behaviour is unacceptable.

Also on the attitude change topic: I'm sure she suddenly has an issue with you post dx, because now you have "valid" or "legitimate" issues, certified by a professional. Which means making things about her her her 20.....4.....7.... isn't logically appropriate any longer, and in order to keep the narcissistic spotlight, she's unable to deal with you.