Rant - bad friends

I have 2 best friends here at school. I live with one of them and she casually asked me how much I weighed since people were making comments about how skinny I look. I told her, not thinking it would be that upsetting since it's technically not "underweight" and she seemed to be understanding that I was really stressed out and it was hard for me to eat. But I think she told my other friend, who recently lost a lot of weight. The thing is, I have always had this eating struggle, ever since I hit puberty. This other girl's issues were very recent. Now this girl doesn't want to be friends with me because she says all I talk about is my weight and I'm so obsessed with losing weight. Now, I never once told her anything about my weight, I try to avoid that subject with everyone...hence having a blog to write about and read about this obsession. I especially try to avoid that subject with her because I know it's touchy and she claims it's all these newfound "food allergies," while it seems like starvation but I am not the one to judge her. But somehow she thinks it's OK to judge me! And the worst thing was, she said that my "newfound obsession with losing weight" was an insult to her and she thinks I am "copying" her. What are we, children? She is so narcissistic that she didn't even notice I was even losing weight, and when someone told her about it, she thinks it's about HER. What on earth? And to top it all off, she said, "YOUR issues are by choice, MINE are out of my hands because of all my FOOD ALLERGIES." Look, maybe she does have all these "new food allergies" (to every single food group imaginable), I have no idea, but I know that sometimes in the past I have lied about having food allergies to avoid eating. So whatever. This really hurt me because I have been struggling with eating disorders for 8 years of my life. Sometimes it's better, sometimes it's worse. But I have been in treatment before and I have spent enough months missing out on life to exercise all day long, to not have to take this shit. What a terrible friend. It just hurts and makes me feel so lonely. I can't believe I even tried to explain to her my situation, and let her in on my past a little bit, just so she would maybe understand what was really going on, but she didn't want to hear any of it and now I just feel like I opened up to someone for nothing and that feels awful. I thought our friendship was worth more than this, but she's done. And I was there for her, never judging her, for all the things she went through, even when I saw her being horribly manipulative to some very innocent people. Even though seeing her clearly go through eating issues was a little triggering to me, it never was a reason to stop being friends with her. You don't desert a friend in need. The real triggers in my life are things like this - BEING deserted, feeling alone, feeling overwhelmed, feeling like a failure, needing something to control. Now I feel like I have no friends and it sucks, because I isolate myself like a hermit since I can't deal with anything and it's easier to just be alone with my obsessive behaviors.