Snape, in an attempt to save Lily, created a potion that kept James and Lily alive when hit with the killing curse, but put them into a coma. When they wake up seven years later, they find themselves on a journey to fix what went wrong: to free Sirius from Azkaban, help Remus learn to live again, rescue their son from the Dursley's, and take on the world together, as a family.

So maybe everything didn't work out perfectly for Harry. Still, most of his friends survived, he'd gotten married, and was about to become a father. If only he'd have stayed away from the Veil, he wouldn't have had to go back and do everything AGAIN.