I definitely think John loved Mary and vice versa. I prefer to believe it was less of a "Here, let me hit you with my love potion arrow" and more, "If we get these two people in the same room, that shit will happen naturally." They never said it was forced, just that they had to make sure it happened, which means I can stay in my happy place of true love despite the preordained crapola the Cupid spouted.

ETA: And yes, to the Jimmy thing. I was trying to reconcile the whole thing and those are some great explanations that I can get behind.