It was the week before my birthday and I entered my parent's room to get something and I guess my mom was in a bad mood or something (which she always is in) she looked at me in a bad way like I was vermin or something so I asked her what did I do wrong (my voice is unnaturally high and I have a loud voice) and she just snapped at me and yelled at me about how I should never talk to her in that way so I ran back to my room and my father was also in the room but he did nothing.
The next day me and my dad were having breakfast and he came to talk to me about apologizing to my mom and cutting her some slack because she was tired. He does this every time me and my mom fight. It's always my mom who's the victim here and never me. I just ate silently and listened to him but I think he thought I wasn't listening so he threw his pizza at me and told me that I was a spoiled brat and that my personality sucked. I tried to talk to my mom after that, I tried to open up to her but instead she shot me down and called me disrespectful.
The day before my birthday I was the one that apologized because I wanted to be happy on my birthday but they never said sorry to me. I got nothing out of them...
I confess that I have slit my wrists because of depression and none of my friends know. I know that I really need help but I just can't bring myself to tell anyone. What should I do?

First off a few things need to be known before you can get proper advice.

1) What age are you?

2) Where is this happening at ? (what state or country)

People here really need to know your age.
Tell your parents you are very depressed and need counseling and if they get upset and shoot you down (financial reasons or feeling like you are implying it's their fault, not all parents handle it well), tell the school nurse. You need to tell someone. A trusted teacher, a relative, a clergy person.

I'm 15 years old

Poor soul!

Hope I don't sound repetitive, but, yes, this DOES count as emotional abuse. You should tell your local counselor or teacher. It is a teachers job to help students, even though it is difficult for them to help.

And remember, NONE of the things your parents say are true. You're the child, THEY are the adults. They have there own problems, they have to be the big kids and deal with it WITHOUT putting you down. Tell yourself that over and over!

Let me know if you need anymore support and good luck!

Deffinatley go to counseling, I know it helped me a lot. Also, if you feel you are being mistreated, and your parents won't listen, go to your school counselor, or a teacher you trust, and tell them what's going on. Things will get better.