Many activists who thrived in the 60s were unable to adjust to the end of what that decade represented. Many of the Weathermen Underground leaders, for example, came out of hiding because their unity against Vietnam "unraveled" as soon as the war ended. The "bad 60s" was also facilitated by the violence that became prominent (Charles Manson, Hell's Angels murder at Rolling Stones concert, etc.).
I'd also like to suggest one of my favorite films, which touches upon the disenchantment of hippies after the 60s ended. Easy Rider, which was produced and directed by (also starring) Dennis Hopper and Peter Fonda, chronicles the journey of two bikers who travel across America on the ubiquitous "search for freedom" and the meaning of America. However they find that the times have changed; Billy, one of the bikers, says, "This used to be a hell of a good country. I can't understand what's gone wrong with it." Anyway, I'd recommend this strongly to those who haven't seen it.