I am always afraid of my wife's infidelity and seek psychological counseling.

Spend energy and time on yourself, not on your wife.

This is a sign of insecurity. Many (psychological) problems of adults stem from childhood experiences and feelings, or are influenced by original ecological families. When they realize that this is a problem, they will seek a solution. If there is a question, there is an answer.

Imagine whether you have been influenced by your original life experience, and then you can analyze the original problem thoroughly. You know you are suffering from it, so you won't repeat this question to yourself. Then find yourself something to do. People's time and energy are limited. If you keep yourself busy, you will reduce your thoughts. Find something that makes sense to you.

In addition, if you trust your wife, you can talk to her deeply about this problem or your anxiety and worry. You are asking for her help, not questioning or blaming her. If you set the tone and the purpose of communication, it is not easy to conflict.