I was really happy in life and then my life took a turn for the worst, I am now depressed.?

I was doing so good in life, I had alot of friends, I was doing good in school, and I was extremely happy in life. Then I fell in love with a girl, which ended on a bad note, lost all my friends and happiness. I experienced love failure, health problems, and betrayal at the same time. I am 23 years old and Iam extremely depressed and cannot seem to escape it. Nothing makes me happy. What can I do to go back to normal, how I used to be.