Simplifications are not always recommendable but I am convinced that most of the personal crises experienced by UFO researchers can be attributed to the psychological disorder called Cognitive Dissonance.
Cognitive dissonance is the growing discomfort experienced by those who believe or promote two or more contradictory ideas or beliefs.
Some individuals, even those with good cultural background, suddenly discover the so called UFO phenomenon and are seduced by the promissory options offered to imaginative researchers. This is the beginning of the "romance" between ambitious individuals of both sexes and the whole spectrum of the UFO mythology, included the accessory memes of conspiracy, cover-up, close encounters, abductions and contactees.
Problem comes when sooner or latter, these researchers, now professional or semi-professional writers and even "public personalities", become convinced that the whole ufological corpus is the "mirror palace" and the swamp. Nothing is real. There are no evidences.
Sources are invented. Sightings are natural phenomena 95 % of the times. Messages from the Extraterrestrials to contactees, are a stupid blend of new age rhetoric and "spiritualism", and the "experts" compete in selling to a gullible public the same old fictions presented as facts.
Of course, the big problem comes when the self-proclaimed researchers are professionals or semi-professionals. Decorated lies repeated again and again are now a profession. The researchers are directly or indirectly compromised with the UFO industry. The market rules, not the truth.
For the professional ufologist there are few options. Either he or she leaves the rarefied world of UFO subculture, or becomes a show-man, secretly conscious that cover-ups, conspiracies, disclosure demands, discredited events and unreliable sources are the world of make-believe. The adoption of an aggressive-defensive attitude becomes a systematic condemnation of all those who contradict his rhetoric. The skeptics are now psy-ops, government agents and dis-informers. The ufologist is protecting his market.
This situation is indeed a source of discomfort and eventual crisis for those who know the truth but are compromised with a fantasy.