Here are some of the original approaches to simulate Sanity in Fudge:

http://www.panix.com/~sos/rpg/fsanity.html

Unfortunately those aren't available under the Open Game License so you'd need to contact the original authors for permissions.

The old Fudge Factor had an article that gave a system for Fear Checks that could  give a character a psychological problem.

http://wayback.archive.org/web/20080516 … hecks.html

http://wayback.archive.org/web/20071024 … sited.html

The Guidline Gazette for Terra Incognita  Vol. 2 had some fear rules that are a  modifications of the above James Wedig ones and had some info on Victorian Age and Pulp Era therapy.

http://web.archive.org/web/200612300539 … aghund.de/

Another Fudge  Factor article

http://wayback.archive.org/web/20060831 … y_mad.html

A Magical Medley has some Sanity rules in the Occultism chapter.

None are OGL.