How do I deal with depression?

I've been battling with depression for two weeks now. My dad who have been my greatest hero passed the veil and left the mortal life. I feel like a part of me is empty. I don't have someone to talk to now, I don't have someone who will comfort me when I'm in big trouble. I feel lost to this very cruel world. I feel so alone and lonely. I feel like the world is beating on me. I've been crying for days, many sleepless nights and tiring days. How do I deal with depression? I already asked for help to some of my friends, but none of them is helpful, even looked on testimonials in a foreign page about fighting depression but still, no effect on me. I need your help.