Bless your heart. I complete understand, since I've been depressed since I was a very small child, and later found out it was clinical depression.
No one in my family was supportive. In fact, no one in my family paid a BIT of attention to the 4 of us girls. Both my parents we alcoholics, so we girls might as well have been the furniture -- at least we would have gotten dusted once in awhile.
I imagine school is out where you live, right? If it isn't, it's going to be soon. You really DO need a professional to talk to. I'm sorry your dad is 'blowing you off.' At least that's what it feels like. Maybe if you showed him these posts, he might sit up and take notice! If he knew that you wrote to Psych Central, he might take you seriously!
You DO need to be evaluated by a psychiatrist or psychologist -- one or the other. But definitely, you DO need to see someone. Have your Dad read these, or just tell him that you're serious about depression and you're miserable and want to see a professional. Tell him that LOADS of teenagers in this country are SERIOUSLY depressed, and need help.
My own granddaughter has been in therapy for 2 years now, ever since she was 15. She's 17 now, and a senior in high school. She has some serious issues, and I'm glad I put her in therapy when I did!
Have a talk with your dad -- tell him that teenagers DO have things to be depressed about, like their future, the shape of the world, and even our own country at the moment, the economy (which is failing) all sorts of things! I hope he'll listen to you. God bless you and please take care. Hugs, Lee