How do I make my best friend realize that there a LOT of people who refuse to date fat people

It's really hard to talk with your friends about this kind of thing because OF COURSE she's going to build you up and cheer you on. If she's really your best friend, she loves you and probably genuinely thinks you're beautiful and lovely and desirable. Even if she understands how you feel and what you've experienced, she's not going to want to risk hurting your feelings by validating it, or it's honestly difficult for her to imagine that someone wouldn't want to date you since she obviously thinks highly of you. Try not to judge her because she's "socially accetbaly" curvy. Good friends love you for you (and likewise, you should love and support her back), and that's a really special thing to have. She's not being malicious, even though it can be frustrating to want to explain your experience.

I'm sorry you've had such negative experiences in the past that you say 'there are people who are literally disgusted by my body'. Having been through the abuse myself with an ex, I know what that feels like. It says more about them than you. You don't want to date those people anyway, because they're shallow and low. You are so so above that shit. Your friend is just trying to help you feel better. Sending you lots of love xxxx

There may be some people who don't want to date us, but trust me there are a lot of people who do. You don't need to make her see anything. You just need to do you and work on your happiness.