Prayers

Do prayers really work? Ever since I was child, I was an ultimate believer of prayers. I believed that if you prayed really hard, your prayers will be heard and they will be granted. But lately, prayers don't work for me anymore. It seems like the harder I pray, the more it wouldn't be given to me. Every time I pray hard for something, it would be taken away from me. So, now I think maybe prayers don't even work at all. Maybe I shouldn't pray anymore so that I would get what I want. Maybe humans just invented prayers to give them hope. It's so depressing to really believe in something all your life and when you really need it the most, it fails you.