In my headcannon, Starlight and Smash was saving all these ponies from a curropt politician that ruined their lives by taking away their loved ones.

In Suger Belle's case, her mother. But since Smash loved Starlight a little too much for her liking, she tricked him to go to a faraway-place to get a wedding cake.

While he was gone, she used a spell on herself to make her forget about him. But the spell was too powerful and made everyone in "Our Town" forget about

why they were all there and thus it turned from a refugee-camp to a cult. That is why Starlight never mentioned Smash when Twilight arrived for the first time.