Most proposal videos are really awful, but that's because they're annoying. This one happens to be more on the "horrifying and baffling" side of the proposal spectrum — horrifying because of the unbridled terror and loud sobbing, baffling because she says yes at the end.
Matt Van Vliet got several police officers to pull over him and his girlfriend, fake arrest him, and then lead him over to his beloved, ring secretly in hand. While she is crying — presumably due to confusion and fright, from being pulled over and arrested for no reason — he proposes, and a bunch of their friends run out from the bushes and start cheering. Classic.