In reply to lex: I don't winter climb, but when on rock...
I mentally rationalise as much as possible. In my mind I am thinking things like
"I've climbed this grade before so I can do this climb"
"That ledge is miles away, the gear will catch me before I hit it"
"This is a hard move but at the grade this route is, there must be either easy climbing or bomber gear straight after so I can use a lot of strength doing it"
"I put in so many micros there that at least 1 of them will hold"
etc. etc. etc.
I think it's all down to fooling yourself (but not badly enough that you end up in a life threatening situation). In the easier grades, even well protected climbs have plenty of areas where a fall would be quite unpleasant so you can't really afford to be concentrating on the fall and the consequences.
Some people find rationalising or ignoring the subconscious recoil in horror easier than others and I think everyone gets better at it with practice.