Make amends, make friends, or make a marriage. The love spell does what it says on the label.
For marriage, you still have to have the amulet. NOT foolproof but it usually works on Jarls and beggars alike, married and unmarried, human, elf, and argonian, but not khajiit (yet). It can confuse your enemies for a second also.
Don't worry, Braith will probably be back to her old self before long. :)