build your own confidence and find friends at work

When I joined my current employer in a Southern town, I was very depressed. I felt like a outsider and my mentor was very harsh. I used to blame myself for everything.
Shortly, I discovered running from a coworker. I feel that if he can do it, I can do it too. With time, I have completed two marathons. Running helps me discover my strength. Now I feel that there is nothing I could not accomplish as long as I try my best.
Also, I branched out to people outside my group through asking for joining their lunch. Don't waste your time in pleasing people who do not like you. Use the time to identify people who have positive attitudes and warm hearts, and appreciate/respect diversity.
Hope that it helps.