TW This girl made fun of me for sh and I have to room with her

TW!! I kinda need to get this off my chest but this girl last year had seen some of my cuts which this was last year I'm trying my hardest to stay clean. Anyway this girl this year saw some of my scars and laughed at me. She told me I had gotten better at hiding cuts and told me that they should be covered. But to her this is so funny and a joke. One of my friends told her off but she didn't stop. The rest of the class she made fun of me. The worst part was we had to do a project on how are summer was, (I was in a phych ward and extremely depressed). So I had nothing to say, she got super *** and decided to do her own thing all while saying I should cut myself. I immediately went to my advisor the next day and requested to change my class. (I actually got a class I wanted to take this year and made some friends so :)) But now I am being forced to room with her during a school trip. I'm terrified she'll see my scars or continue to make fun of me. The teacher in charge of this loves her to and I don't want to tell them what going on because all they will do is tell the councler and our counclers are horrible human beings. I have no idea what to do and its just a *** situation.