If you're cutting, you don't need to feel ashamed. Such behavior is more common than you think. But, like others have said, you should get in touch with a psychiatrist. There's only so much that a GP can do. Look in the phone book if you don't want to go to your parents about it. There are people out there who would just love to help you.
I just want to say a couple of things though:
- I know what depression feels like. I disagree with mithrandir in that I feel that the cause can be either experiential (some event or series of events in your life, abuse, emotional trauma, etc.) or it can be chemical. My brother-in-law has suffered from chemical manic depression his whole life, and only recently has he sought the assistance of medication to improve his quality of life. I think he would have been suicidal if he didn't have a wife and two children to constantly remind him that he is loved. In his case, an SRI really helped give him the push he needed to beat it.
- I know this gets said a lot, but I hope you don't see it as a cop-out... suicide is a permanent solution to a temporary problem. Killing yourself leaves you no way out, no turning back. You have a full lifetime ahead of you, and ending it before it's hardly begun would be a shame. IIRC you're in your late teens/early 20s, and I have to say that those years can be awfully tough. But things get so much better once you're in your mid-twenties. I'm 24, and the problems I had as a teenager that seemed so huge are but distant memories now.
- Mithrandir does have a point though in that medications aren't a panacea. You've got to want to feel better, want to change for any solution to work. Zoloft or any other SRI can help you overcome what may be insurmountable otherwise, but the first step is loving yourself enough to want to get better. So, that's what you need to work on. You may think that no one cares about you, but that simply isn't true. It's just that without enough love for yourself, it's difficult (if not impossible) for you to perceive love from anyone else.
This world can be an incredibly cruel place, but there are good people out there who really make the rest of it bearable. They are difficult to find sometimes, but you have an entire lifetime ahead of you to find them, and you will find them if you try.
Your life is precious... the sooner you allow yourself to realize that the sooner you'll be on the road to recovery. You can overcome this--trust me.
Please IM or PM me if you ever want to talk... anytime.
P.S. If you aren't comfortable with talking to a counselor/Dr. right now, PLEASE go to a bookstore or library and find the book "The Road Less Travelled" by M. Scott Peck, M.D. I'm not into most books in the "self-help" category, but this book honestly changed my life. It took ideas that had been rattling around in my head my whole life and made sense out of them. I know trusting in someone else's book recommendations isn't always the best way to go, but if any book can help you this one can.