Being totally lost...

My life got crazy for last days. Last 5 days was like hell to me. I lost my best friend. I know that it doesnt sound like really serious, but for me it is. I'm totally alone and lost now. I had friendship i guess everyone would dream of. Really. But now i dont. Boom and its gone. I tried to ferget it, not to think of it. I went to club, i was hanging with people from work all the time, even tried to find GF, but it didnt help, i still think about it and everytime i see him online i just want to write hi! how r u?, or have sweet dreams! see ya tomorrow!  but i cant, i'm just not sure if i still can torture myself. i walk spesially near his house everyday so if he goes out i just see him a little but does it sound normal? i have grey hair again..is it normal for 18 years old to have grey hair second time in few month? is it normal fo teenager not to sleep or eat because i'm just not feeling like even thinking about food. I dont know what will be next crash in my life! I always ruin something! First my american bro who thinks that i'm too emotional to everything and i dont feel like he really want to talk to me, then my best frind who thinks that i'm liar, my other frinds who thinks that i'm gay because of my style of clothing, my relationship with mumm which is always have problems, everythink i touch is ruined... what sence of doing it again. I'm probably just need to close myself in and live in my own world... sad but true. I need to be loner so i cant hurt anyone. I dont have other choise. It will be hard for me, really hard. But iguess i have no other choise!