Damon decided he wants to take the cure for himself and have a human life with Elena…
But, we all know Nina is leaving the show and that scene with them on the aisle and looking at each other during Alaric and Jo’s vows was such a goodbye-type scene.
It was almost like the TVD writers were trying to foreshadow this season’s ending and say, ‘Let’s have this wedding-esque scene, kiss, and love scene between Damon and Elena, since this is gonna be the last time they’re together and a wedding between them is never gonna actually happen on the show.’
Kai coming in only confirmed my thoughts. With Elena getting hurt in the destruction, that final shot of her lying there on the ground, and the fact that next week is the last episode of the season and Nina’s last show, I think that, since she’s human again, Elena will die from the blast caused by Kai and that’s how they’re going to write nina off the show.
And Damon won’t take the cure in time before she dies, nor will he want to because one of the main reasons he wanted to be human again was to live a human life with Elena. So, Damon will stay a vampire (Thank God!), grieve Elena, and live forever with Stefan (Team Salvatore!).