"Against Refusal" by naiad
When Aragorn leaves to find a viable route, Frodo reaches a decision about his own path, hounded by doubt, temptation, and enemies, real and imagined.
A lot happens in this fic, and most of it is in Frodo's head. Very interesting exploration of trust in oneself and one's companions.
One chapter. No reader warnings.
on Stories of Arda
http://www.storiesofarda.com/chapterlistview.asp?SID=4553