Solution I found on google:
Get married and have a ceremony at the castle and pick the most expensive ritual.
Q: Where can I find a person to marry, everyone's Dead?
A: Find Elise or Eliot in Bowerstone Industrial and Marry them if you did not kill him/her in the beginning of the game
Q: Where can I find a wedding ring, every one's dead?
A: Go to a online game and buy a wedding ring or loot houses until you find one.
AND WHEN UR MARRIED YOU SHOULD SEE PEOPLE TO RE-APPEAR AND ALSO THEY WONT HATE YOU, THEY WILL HAVE A NEUTRAL FEELING ABOUT YOU INSTEAD OF HATING YOU SO ITS LIKE THE DARKNESS NEVER CAME.
You can also get people back by playing lute or by sleeping for 14 days there are many different ways to get people back but these methods are the top 3 and, if 1 method doesn't work try the other 2 and they should work fine
Sorry for the bad language and capitals, i just copy pasted and didn't want to edit.