How do i cope with the loss of my dog, my best friend?

i just lost my best friend, taylor thursday night. one minute she was with me at the computer and the next i heard her barking outside. i thought that maybe my fiance had tied her outside to go potty but when i heard the loud exhaust of my fiance's friends truck her bark getting further away i jumped up and started calling her back.. it was too late he stopped just across the street from my house and said "bad news"... ive never felt pain like this before i started bawling hysterically pleading to god to save her...i wasnt going to go across the street to see what happened but after a few minutes i felt something in my gut that said i should say goodbye... i got over there and she was still breathing. i held her and pet her as she laid there.. i dont think she felt any pain though.. which is a great relief.. we believe she broke her neck but she also had some internal injuries.. i told her to just close her eyes and let go..and she did.. :''''( i cant stop crying.. i dont want to do anything with my life anymore.. i dont want to wake up or go about my day.. i hate not having her around. ive never felt a hurt worse than this and i hope to god i never do again, but how am i ever supposed to love another dog when taylor was only a year and 3 months old, ive had her since she was 7wks and i hurt this bad... how do you overcome the pain? how do you start to live your life again? the hole in my heart makes me feel like i cant breath sometimes ive never shed so many tears.. i wake up early still to let her out, and at night when shes not in bed i feel for an instant i forgot to let her in..when im away from home i come home expecting her to greet me.. i dont want to wash my truck cause theres a muddy paw print on it from her.. i just wish i knew how to cope with this.. i know that if i just would have been paying more attention and didnt let her go downstairs she would have never snuck out of the basement and chased that truck.. i want so bad to make the pain go away but i feel like that day is so far away..