In a play that kind of "love destroys" arc can work really well. I'm not a big fan of it as a general trope since it tends to make me think the characters are being self absorbed idiots (you really can't think of any other person on earth who could make you happy? you either haven't met a lot of people or you have no imagination). Anyhow, that's beside the point, what I actually wanted to say was, I'm very leery of it in LARPs. It tends to lead to a hyper focus of one character on another character (assuming both in the pair are PCs) which can stunt the obsessed character's other plots and relationships. If you end up casting someone who's not super into the angsting, that can go very wrong.