Fear of death help????

It all started on a wednesday. I think it was may 25, but anyways the day went really awesome, but that night randomly this thought came into my head that when people die, its just nothing forever, and it was really wierd, because it really freaked me out and made me sick to my stomach. I was hoping that I would just sleep it off, but its kind of become an obsessive thought, and I started having these little anxiety attacks during the day. It got better to the point were I wasnt really getting freaked out, but then I found out about my friend who killed himself Saturday and things have been getting worse. Idk its like now I don't have motivation to do anything, I have no appetite, and everything feels pointless.. I've been trying to believe in God, but there are times that I can and times that I cant, and it feels hopeless