There is something wrong with you if you never fear. The psychological incapability to feel any fear is a symptom of an extremely rare condition called Urbach-Wiethe disease. As long as the brain is wired correctly, fear is a normal part of life.
Take, for example, St. Paul. He was not embarrassed to admit that he felt “fear and trembling” when he came to visit the Corinthians for the first time (1 Cor 2:3). And he praised the Corinthians for their “fear and trembling” when they received St. Titus for the first time (2 Cor 7:15). He encouraged slaves to obey their masters with “fear and trembling,” (Eph 6:5). His advice to all Christians, in fact, was that we work out our own salvation with “fear and trembling” (Phil 2:12). He used that same phrase four times.
The psychologists and St. Paul agree: fear and trembling are normal, natural parts of a healthy life. The important addition today from St. Paul is that the spiritual life is no different. It is best for us to have fear and trembling as we work out our salvation. If you feel neither fear nor trembling in your spiritual life, I recommend praying Psalm 55. I recommend it not to frighten you, but to give you a way to unite yourself to perfect prayer. Jesus Christ himself, like all Jews of His time, would have prayed with this psalm, including the part that describes being overcome by “fear and trembling.” Allow yourself to have fear, then help it to grow within moderation, keeping it focused on your salvation, and uniting it to Jesus Christ, true God, and true man.