No Married Persons

[Inziladun]

I think Legate covered it pretty well, but I would support his statement about Boromir with this:

Boromir...beloved by his father, was like him in face and pride, but in little else. Rather he was a man after the sort of King Eärnur of old, taking no wife, and delighting chiefly in arms...

ROTK Appendix A

Seeing the Fellowship through Elrond's eyes, that all were "called", I would also say that the collective unmarried status of the Fellowship would have been one of the criteria for their inclusion in it, for the reasons Legate stated.