The Fellowship of the Ring and Nominalism

I've been thinking about nominalism again and the way groups can either be collections of individuals or a unity of members, and my mind naturally wandered to that premiere metaphor of the church, the Fellowship of the Ring.

I began wondering, in the LOTR, at what point is the Fellowship broken? Of course, there was no better authority to answer this question than our daughter, Susan, so I asked her, and this was her wise reply:

The last chapter of Fellowship of the Ring is called "The Breaking of the Fellowship." In it, Boromir tries to steal the Ring from Frodo, Frodo and Sam flee, and the others scatter about trying to find them. Later we learn that Boromir dies and Merry and Pippin are scattered. So there are severals ways it could have been broken: Boromir's attack on Frodo, the physical separation of the members, or the death of one of the members.

However, is "breaking" the same as "ending?" In the very last chapter, The Grey Havens, when they're getting ready to sail away, Gandalf says to the hobbits, "...on the shores of the Sea comes the end of our fellowship in Middle-earth." And in the histories in Appendix B, the last entry says that when Sam had sailed away, and Aragorn, Merry, and Pippin had died, Legolas and Gimli also sailed West together, and "when that ship passed an end was come in Middle-earth of the Fellowship of the Ring."

So a few things may be concluded:
-The Fellowship was broken by death, strife, and/or separation.
-The Fellowship still existed in Middle-earth (though in a fragmented state) so long as some of its members were living there.
-We are left with the possibility that the Fellowship still exists, but not in Middle-earth.