Uncertainty

It was perfect, Princess Celestia was dating her immortal student Twilight, and no mortal pony would ever have her. Tempest, finally free of her guilt, arrives at Ponyville to learn more about friendship from Twilight and her friends. Tempest never stopped loving Twilight, and Twilight realizes that she's been missing out on the feeling of true love.

Princess Celestia isn't okay with this turn of events, not in the slightest.
Cover art done by snobbleweb!

This story is finished, but there might be sequels, prequels, and alternative endings in the future to wrap up the unresolved subplots in this story. Check out my new MLP fanfic, Shooting Star!