So I have this problem - what should I do? Should I talk to someone?

Hello everyone, I hope you're doing okay.
So this thing started in the beginning of the school year (which happens in March in my country). I'm fifteen and I'm going to be a freshman next year, because I failed one year and stayed home last year because I was way too anxious to leave home without having a panick attack and almost dying.
So yea, I finally decided to go to school again and have a normal life. I'm going to night school, which means I can finish 7th grade in 6 months and then 8th grade (last one until high school) in other 6 months. Next week should be my last week in 7th grade, but I think I'm going to fail again because I don't show up at school - because of anxiety!
I'm tired of doctors and medications, because they make me numb and weird. So yea, but I was pretty confident at school until I met this guy, he's something like 16 or 17 and he's my classmate.
He smokes, drinks and does drugs and keeps teasing all the girls at school. But the girls like it, they LOVE it when he and his friends make sexual jokes about them. So he started to make those jokes about me too. All of his friends call me his girlfriend, but I'M NOT. I don't even know his freaking name.
I already told him to stop because I makes me uncomfortable as hell, but he just laughs and says "I know you love it". It's making me depressed again and I don't even want to go to school anymore because everyone keeps staring at me and laughing, asking sutff like "hey, where's your boyfriend?".
I know he doesn't do that because he thinks I'm pretty or because he actually likes me, he does that to every girl because he thinks we are just a pair of boobs and someone he could have sex with and nothing more. And also, I hate it when people stare at my body because I used to have an eating disorder (which started when I started to "grow up", like my body started to change and stuff, and the other girl's bodies didn't, so I stopped eating to lose weight, especially from like my thighs and stuff)
I'm afraid he could try and do something with me, because he is bigger and stronger. And I'm afraid of actually talking with teachers and such because they're going to talk to him and he is going to like trying to get "revenge" or something, since he is always drugged.
I'm NOT going to tell my parents because they're going to be all like "Wow, you're 15! You should get used to sexual things!". Also my mother says I'm overreacting and being "dramatic" with this whole social phobia thing - and she knows I've been to a lot of doctors, therapists and stuff.
I'm afraid of losing antoher year of my life because of those people, what should I do?

What a mess, Little One. But not too late. Almost. But there's a little time, but you must work very, very hard and come to terms that your brain has not finished growing yet and if you do not take its growth in your hands, then these negative occurances will shape it - for a long time. First, you did not 'used to have an eating disorder.' You still do, and chances are high that as long as you take a breath, you will have some sort of issue with body/food or both. If you make good, strong decisions now, the ED may rest under the surface so that you have some peace, as I do. Secondly, your parents sound like people you don't feel able to talk to. Who CAN you talk to? School counselour? Your therapist? Can you register for home schooling? Or another school while you are getting your social anxiety under control? Is inpatient therapy with education an option. You've got to take the bull by the horns, and speak what you need. If you don't know what you need, find the person you can talk to in confidence who knows about these matters in your country, and ask him or her what the options are for a student like you who needs to catch up but is in danger of flunking. What do they do for the teens who are physically ill and cannot attend school there? Whatever they do for THEM, you should have access to. Your troubles are not healed yet, you don't feel safe yet. Whoever your trusted ally is, they need to come to your side and be your advocate and speak these things. Just because your issues are not seen like a broken leg or a tumor, that does not mean tht you are healthy enough yet to go back. Do whatever you can to discover the options and gain a respectable adult to be your ally. Maybe you really need deep hospital residential care to gain the insight and confidenc to return - and in the meantime have your school work sent there. I don't know if that is allowed where you live. But I assure you - your troubles are not impossible. And you must kill this eating disorder, or at least make peace with it before it terrorizes the rest of your life. You are perfect the way you are. I promise you that. Humans drag each other thru the mud, making us think we need to do this or that to ourselves. Your ED is the thing you control...once you get control over other aspects in your life, you won't need to control your food so much. But it is a dangerous addiction. And it can destroy relationships with people you want to love and who want to love you back. You will be ok because you were born ok. Shake off the worries and the need to worry about so many things. One thing at a time, and with the help of the person who you trust. There IS an adult who will help.