Why do I want to die so bad?

I am a 17 year old male and it seems that everyone around me that's my age is so chipper and eager to see how their lives will pan out; I share no such sentiments. Every day when I go to bed I pray I won't wake up, I don't care how my life will pan out; all I know is that it will be filled with suffering and misery, I don't care about going to college or taking SATs or how my grades are, I just want to leave this stupid planet. For some reason, I don't have the desire to commit suicide directly; I am somewhat religious so apparently I'll go to hell if one day I decide to cut my wrists or hang myself. That aside, there probably will be people that will miss me if I'm gone; it's just hard to care when they're all the happy ones and I can't think about anything other than death. I just really can't help but feel there is no purpose to life; I hope a plane falls on me. Why do I feel like this? I wish I didn't, I just can't see the glass half full.