This video from Dalarna University offers some good insights into the process of self-directed language study.
http://www.youtube.com/watch?v=_GCLYYNmu5g
Particularly helpful is the 7 stages by which one can measure one's progress in language learning. It is only in the last 2 stages where one can be considered "fluent" but that should not detract from the success of having achieved any of the first 5 stages. A definite must-watch for anyone about to embark on self-directed language learning.