I just finished reading Tony Doyle's rather excellent book about his time spent flying Meteors, Vampires, Gnats and Lightnings in the RAF.
He mentions somewhat casually mid-way through that was always scared of flying, and that he would be anxious from the moment he awoke on a flying day.
At the time he was display flying (Gnats and, later, Lightning solo) it almost drove him to mental breakdown. A couple of years convalescence on a ground tour saw him return to a better state of mind, but he remained very anxious with high altitude and night flight.
Doyle explains that his own ejection from a dying Lighting had made matters worse, as had seeing the two previous Lighting solo display pilots buy the farm, but it is clear that he persevered and flew many hours over 20 years despite the fact he was frightened.
How common is this among military flyers?