every job i.v ever had, about 6 of them, there was always at least one of them like you describe. i actually quit a job once when i was a teenager, because of it. i learned to stick up for myself, a lesson waiting there for me, not to let these people get to me, but i stuck up for myself since then. it does take courage because we fear losing our own jobs, but maybe you could say something to the person and confront them on their misbehavior toward you and let them know they make you feel uncomfortable, alone. do something funny like asking them to share your breaktime with them, or ask them out for a drink after work. i know i had alot of friends at one of the jobs i had because i asked everyone out to the bar across the street and we all started meeting each other there, i didn't have a great job like anything special but was a menial produce clerk, going to school too. the school people also wanted to join in and it was a blast every weekend. i never had a happier time in my life, at such a menial job, but lots of love spreading around and people just having fun.