i don't trust the Godness, i still think this love is all set up to make her stay away from the black haired guy. there is magic, so there must be love magic too.
all the heroes must keep her away until X years have passed, probably after a certain period the demon king dies.
everytime he resurrects, she does too, but so the hero together with her, so that the hero can do his job (making her fall in love with him and keep her away and kill/seal the demon king).
that is why they left her in the other lives, because the time had passed, because they didn't have carry the responsibility anymore (they were free).
but now since she moved somewhere else the hero had to come back and make her in 'love' again.
also maybe it has to do with her love, like she makes others stronger, she must be special somewhat, her existence must mean something. or else she wouldn't be going through such pain in ass.
i don't trust that guy, neither do i trust this new god. the girl is too fucked up in the head for them to be doing any good.
if they did the job right she would be already happy after so many lives. not like this is her first live with a hero...