Im also confused. But i settled with - 'Ill kill myslef' interpretation.
Coz he said Swanton will have a new king- he is the king of swanton so its either he will step down or he will die coz dont kings have immunity from being prosecuted even if he personally killed someone; and
that while saying he will return the last gift she gave him the images presented were those when he still believed that Chloe is dead so he meant he will kill himself just like how chloe made him believe she died. But not in the Fake dead way...like the dead 'dead' way coz chloe wont go after him if he fake his death anyway.
will return the last gift she left him? what?? does he want to return her his dead body like how she returns hers to him?? is that what he meant by a new king too because he's planning on dying? or maybe he is planning on dying but not really dead, like what Chloe did?