Like Trieste said, coming forward really is admirable and brave. Getting help from a professional takes a lot of courage as well, and you've already shown you have that courage. But, as she said, a professional really is the way to go. I've been there. *hugs* Depression is not always something that one can pull themselves up out of by sheer force of will alone. Sometimes, there is a chemical imbalance involved.
I have had dysthymia, low grade depression, which is also mixed with bouts of major depression since I was five. I too felt guilty and like a failure due to these feelings. It took awhile to realize that it wasn't my fault any more that if I had had diabetes or heart disease. I couldn't will those away, nor could I depression. But, it was only with the help of a medical professional that I came to these realizations.
There are Mental Health crisis hot lines that you can call who can help you. Crisis workers are there can speak with you, and that may be able to help you get connected with a professional. The number for our counties crisis hotline is listed on the internet. I just typed in the county that I live in, state, and crisis intervention hotline.
Here is the number for the National Suicide Prevention Lifeline at 1-800-273-TALK (8255) or the National Hopeline Network at 1-800-SUICIDE (1-800-784-2433).
Also, you mentioned that you were in school, many schools have mental health resources available to their students. You should be able to find out via student services.
I wish you the best of luck, and do know that I care about what happens to you. Please let me know how you are.