Sorry to hear buddy. You'll find lots of support here, most people that have had pets, have had the unfortunate incident of losing them. I have had 2 close dogs pass on me. One lucky passed on during the night, the other was pretty painful. I was in 5th grade and it was the first dog/pet that was actually mine ya know, well I was at school and I got a call from my mom saying that when she went to let the dog, she ran out to fast she didn't even get to open the door all the way, and ran directly out into the street and was hit by a car. She suffered for about an half hour/hour before she finally passed on. I didn't blame the driver, she was quite a nice woman instead of just bolting like most do she got out and helped my mom make the dog comfortable as she went which helped b/c it shocked my mom and I don't think she woulda be able to do it alone. I was at school and got the phone call, I remember I ran out the office and ran home as fast as I could like if I got there fast enough she wouldn't be dead anymore, but I was too young to understand.
So hang in there buddy,if you ever need support, I know that anyone here would be willing. Wish you the best.