starting to affect work

so i work in a restaurant and iv pretty much always been the odd one out, most waitresses are pretty and thin and fashionable in stuff, iv been workin here for ages and iv never once felt like i fit in the the waitresses or bar staff but i do fit in with the chefs which has really made the job easier, the headchef and second chef i am both really close to, all the chefs seem to be kinda protective if me and treat me as if im theyre staff not as if im part of the front of house staff and i rely so much on this to get me to work, i know that one of them will always be there to give me a cuddle when i get to work, but one of them is leaving soon and he has started to be kinda mean, like, he hardly talks to me and he yells at me more and doesnt help yet i still feel as though i have to do as he says and i still make him tea and i do loadsa jobs that he doesnt like so that he will like me again, i vac the floor, i empty the bins and wash the back yard, all the jobs he really hates yet he isnt being any nicer to me, it hurts so bad and when he just responds so coldly i always spiral into a crappy mood, and i have cut myself several times at work recently often triggered by something silly he has said, i dont want him to leave, i dont think i can work there if he leaves , i dunno what to do, sorry for the huge rant! Lol xx