Why do i smell like feces

I'll begin this by saying I've started smelling like poop in seventh grade. I am a junior now in high school, and this has ruined my life. I can't gain any new friends now because of this stench. Often many of my classmates make rude comments about my smell. When I sit next to someone they put their hand over their nose to cover it or they sigh very loudly. I feel so guilty. I have a boyfriend since eighth grade and I know he knows I smell. I know how much pity he feels for me, it's horrible. For my birthday he's given me body mist and lotions. I wear them, but it just makes it worse. I'm so done with this smell, I can't do anything without someone turning their head from me. I usually have thoughts of killing myself because of this! I also did not eat for 2 months because I thought it was because i wasn't cleaning myself well. I have a healthy diet now, but it doesn't help. What sucks the most is when my period hits I smell horrible. I myself cannot smell myself but others can. I shower two times a day, and always brush my teeth and wear deodorant. I'm afraid of telling my doctor about this, because they might laugh at me. Please, help.