Have your friend read this.
https://notdoneliving.net/openletter/index.html

I don't believe that is a best friend. A best friend will listen truly listen and not judge but will be understanding. Im so sorry that you've been friends that long w/o her truly listening to you. People on this site will be understanding cuz they know how you feel. We're here for you!

Sje wouldn't be a best friend for long.

I don’t think that’s a very good friend let alone a best friend. I know there are a lot of people that don’t beleive fibro is real. I’ve been lucky, my family and friends all support me and understand my struggles. I hope when you said “ex calls it exhaustion” you mean ex as in the one that doesn’t believe you. You don’t need to be around negative people. I hope you have other friends and family that support you ❤️

It really is such a "downer" to have people who supposedly care about you not believe what you're telling them. To some people, if you can't cure it by taking a pill, then it isn't real. Just remember the people on this site who DO believe you and try to just let her comments go in one ear or out the other.