There's some basis for this phenomenon, The Rambam (De'ot 1:2) discusses going from one extreme to the other in the process of teshuvah, a healthy person will gradually correct this behavior and find the middle ("Golden") path.
A friend of mine became a BT, was way too extreme, couldn't stack the seeming hypocrisy of the FFBs not doing everything to the T, and frei'd back out.
Shame that he didn't find the middle, but he wasn't comfortable with the middle I guess.