This is why one wise person said that there is no such thing as a solitary Christian. We are the Body of Christ, the Lord sent them out two by two, we are obliged to celebrate the Holy Mysteries together every Sunday and on important Holy Days because God means for us to be made into saints by living our Christian lives together.
The process you are faced with is the process of grieving. You are in mourning because you have lost something your heart was set on. Even if you experience a change of fortune this one time, this is a process that you will have to go through many times in the course of your life, because serious losses are a part of life. This will not be the first time you are denied what you have the inner passion to achieve. There will be more heartaches down the line. It will not be the first time that you will have to use some version of the Serenity Prayer:
*God grant me the serenity
to accept the things I cannot change;
courage to change the things I can;
and wisdom to know the difference.
Living one day at a time;
Enjoying one moment at a time;
Accepting hardships as the pathway to peace;
Taking, as He did, this sinful world
as it is, not as I would have it;
Trusting that He will make all things right
if I surrender to His Will;
That I may be reasonably happy in this life
and supremely happy with Him
Forever in the next.
--Reinhold Niebuhr *
This web site gives a very brief overview of what I mean: memorialhospital.org/library/general/stress-the-3.html
Learn how to cope with this deep hurt now, and you could spare yourself a lifetime pain.
TheRealJulianne gave you some very good advice, but that is the first line of treatment for heartache. If you have tried it and it didn't work, well, that happens. That is nothing against you. Just as very good antibiotics don't always work, sometimes time-tested advice does not work. Since your case has gone on so long as it has, you may need to move onto a second line treatment. Because of how serious depression can be, especially when combined with the brain chemistry of late adolescence or early adulthood, I think you need help to decide whether more serious intervention is in order. Because of how long this has gone on and how serious the consequneces will be if you leave serious depression untreated, do the mature thing and proceed as if this is too big for you. If it is not, it will be like going to the emergency care only to find that what you thought might be a heart attack was really indigestion. When the symptoms are serious, better safe than sorry.
A deep unhappiness that goes on for months is serious business. It can change the chemistry of your brain. I could give you lots of advice, but you need to confide in someone who will take your situation seriously. I don't mean someone who will get very upset or run around waving their hands, but rather someone who will not simply say, "Get over it." I mean someone who will say, "Try this, but you need to keep in touch with me about how this plays out. We need to keep an eye on you."
If advice from someone close by doesn't help the cloud lift rather soon, find someone with the credentials to help you learn how to cope with bouts of depression, who will make sure you get medical care for that if necessary, and who will be your support as you go through the process of bringing your particular heart through times of pain and difficulty. Usually your school or your pastor can help you find this person, if your parents don't, but I'd start by talking to your parents. If your parents don't see your problem as serious, though, verify their sense by talking to those other adults I suggested.
Talk to a real person about this, and do not give up until you find someone who takes your depression seriously, OK? Do not accept "there, there, you're just 14." This is not something for a 60 year-old to manage alone, let alone a 14 year old. Anyone who does not get that will have to be your support on another round. As for this round, keep looking, and consider that a moral duty, just as you would if it were another poor soul other than yourself who was going through this.
If you ever consider harming yourself or giving up, promise God that you will immediately seek a person with professional experience in helping people through depression. I mean a no-exceptions, despair-is-not-an-option, I-will-avoid-this-sin-with-all-my-might and I-will-avoid-the-near-occasion-of-failure promise.