I don't see how Scott chose Emma, everyone will have his opinion about it but guilt, remorse, our conscience and our morals are things that allow us to do things or not and are strongly attached to our personality, it's thanks to them we don't burn the car of the guy we hate or we don't cheat on our partner or we just don't kill another person. If Jean eliminate the guilt of Scott up to the point of making him don't worry to kiss his new lover in front of the grave of his recent death wife it is clear that it is something big not something as simple as simply to overcome the time of mourning quickly .
Even if Scott does not love Jean anymore he will continue to respect her, it is not in his character to commit such a great lack of respect and less to the one who supposedly was the person he loved the most. not from my point of view what Jean did was not something small was a movement that modified the personality of Scott to do something he didn't want, maybe she did it for the good of everyone, but that does not make that morally wrong.