My life feels like a mess. I need support?

I am 14. When My mom and dad r always getting into big fights, my mom storms out and leaves for a couple of days and avoids both me and my dad, and I am left helpless not knowing what I did wrong? In this case it's not as bad, but my dad is away and they got into a fight over the phone. I over heard wat was going on and it really hurt me when I asked my mom if everything was ok and she told me to leave her alone. They are always so busy with work and I try and stay out of their way as much as I can. My mom and dad don't know this but i sometimes try to make myself purge bcuz I need something to make me feel better. I hate the way I look, and sometimes I really just want a mother to daughter time to talk to my mom about things that r on my mind, but when I do tell her things she gets all worked up and annoyed. I have come to a point where I can't tallk to them about things anymore and have resulted in going on this yahoo answers thing to ask advice from strangers ( not to be rude or anything). I feel that I want to be treated younger bcuz my parents r always telling me to grow up more but it's hard enough being a teenager. I feel like I in an oversized body that doesn't belong to me.