Need Personal advise

Actually they were 5 one was my class mate and others from other classes all including me was in 1st year. One day these people entered in my class whatsapp group and the started a voice call and it was at night and I joined in between the conversation I accidentally said a bad word not soo offensive.but they took it as an assault and hit me .I was not in hostel that time I was coming after a bday party and these gygs were waiting for me outside my hostel.then they beat me up it was about 1:00 midnight.then some of my seniors heard about this and made a peacefull compromise at about 3:00 am that day.but I was the one who got beaten by them. Then after that incident I lost my confidence.i am actually an introvert person actually trying to become an extrovert.but this incident tookall my confidence and no I am trapped I lost my confidence my attitude i fear everything now , even after about 8 months I still feel taurma about that incident. I can't forget that incident .now whenever I see those people i fear them and ran away like a dog. If I see there face my mood for the whole day is gone