Describing what this is show is like can be difficult becasue it’s in a very unique category of theater. To give you a reference point, here are some shows that are similiar to How We First Met:
Playback Theatre – Playback Theatre was founded in 1975 by Jonathan Fox and Jo Salas. Someone in the audience tells a moment or story from their life, chooses the actors to play the different roles, and then all those present watch the enactment, as the story “comes to life” with artistic shape and nuance. The re-creation of stories is often non-naturalistic; actors often use metaphor, narration, chorus, genre, movement and song.
LifeGame – Created by legendary improvisational teacher Keith Johnstone and performed Off-Broadway by a very imaginative UK theater company called Improbable. In the show they interview a guest onstage and then transforming that information, there and then, into a magical piece of theatre using improvisation.
Spalding Gray‘s “Interviewing the Audience” – Spalding Gray, who was most notably known for his monologues, performed a very moving and interesting theater piece where he would interview audience members live on stage about their life.