He handle that gently since he once crushing on Rarity.

... So Twilight confesses to Spike that she loves Rarity.

Spike, who's had a crush on Rarity since the day he's got into Ponyville. And... It's not just that Spike isn't heartbroken or upset, in the ways stories that don't want Spike "in the way" write his feelings, it's not even brought up.

That's weird, and not really the only part of this fic that doesn't mesh with canon very well.