Example - one popular way for shy people to try to meet others is through the relatively safe venue of personal ads. Women's personal ads, however, regularly call for attributes in men that I don't happen to possess (height and slimness the most common, but every woman is different). Just reading a few such ads is, literally, enough to leave me feeling physically ill.
It takes very little to set me off. A bad one is hearing a woman say how much she likes football players, construction workers, men wearing Doc Martens, chemical engineers, or anything else that doesn't match me. Another bad one is hearing about the sheer ease with which some women find relationships. Some have literally never gone more than a few weeks without being involved with someone, since puberty. Seeing couples doesn't help; it just seems to taunt me as a reminder of something I've never had and probably will never have.
Women are all-powerful, goddesses whom men must beg and grovel to win the favour of their scarce affections. Capricious they can afford to be, secure in the indomitable strength their beauty gives them. Why should they deign to select a timid, shy loser afraid of his own shadow, when they are all surrounded by a crowd of taller, slimmer, handsomer, more dashing prospects?
Such is the nonsense my fears feed me. I try the usual solutions for this (deep breathing, Rational Thinking etc.) but the fear does not listen to reason, does not listen to logic, insists on pushing its mad course, denying responsibility, denying any evidence that does not satisfy its twisted conditions.
And thus do I starve to death in the midst of plenty.