It's no secret that many JW marriges are loveless. They stay for fear of DFing.
Umm they are not supposed to marry for love either. The official doctrine states that they are to marry in order to (help, strengthen, fulfill I'm not sure of the exact word they use but there's a few sinonyms for you) augment the husband's ministry.
I couldn't believe it either but that's the "official" stance.