A 40s experience is so different than when you are younger. At this age, most men are full of emotional history, broken hearts, divorces, or long-term disappointments. People are no longer as quick to trust, not because they do not desire to be loved but because they are now wary of it.
These are not reasons to blame women and they have to do with emotional exhaustion and altered anticipations, and wisdom gained with time.
Past Emotional Betrayals

A good number of men around 40 years have been betrayed, lied to or their promises have been broken. Such wounds do not fade away easily. The past pain creates a defender in the individual even when a new person comes in. The aspect of trust is dangerous as the memory reminds them of how it hurt so much in the past.
Divorce Trauma

Divorce may sever credibility. Men are afraid of making the same mistakes, which are caused by losing emotions, financial pressure, and stress associated with the law. becomes more dangerous than thrilling. They are afraid to risk once more and lose everything in the process.
Fear of Being Used

Other men fear that they are appreciated in form of stability, money or security rather than themselves. This is a fear that makes them doubt intentions at the beginning. They desire real attachment and not conditional love.
Mixed Signals in Modern .

Difficulty in trust is caused by inconsistent communication, ghosting and undefined intentions. Men who are 40 years old are not used to and it seems to be confusing and tiresome nowadays. They emotionally withdraw because they are not sure of the next step.
Emotional Unavailability of Ex-Partners.

Frequent liaisons with emotionally unavailable men can make them cynical. They begin to anticipate emotional barriers rather than receptiveness. As time passes by, hope is substituted by caution.
Being Compared to Exes

There should be no continuous comparisons with previous partners which may harm confidence and trust. Men do not want to be judged against the past of another person but how they are at the present time. Comparisons render them incompetent and invisible.
Fear of False Promises

There are men who have had big promises that never materialised. Words alone eventually cease to be dependable. They no longer seek sweet talk, but consistency.
Loss of Emotional Energy

A large number of men are emotionally exhausted after a few years of relationships, work pressures, and duties. Trust does need power which they might no longer have readily. They become slower than they used to be due to emotional exhaustion.
Fear of Second Mover Agenda.

Men are afraid of finding out the expectations too late-marriage pressure problems, the lifestyle expectations, or the emotional needs that were not talked about at the early stage. It is dangerous to be surprised. It makes transparency more significant than romance.
Problem with Trusting After Infidelity.

Cheating also causes emotional scars that are permanent. Doubt may lurk in the background even in a healthy situation. When betrayal has previously destroyed it, trust is a long process.
Emotionally Displaced with Not a lot of effort.

A few men have been thrown away and have been easily replaced in previous relationships. This builds fear of insecurity of emotions. They are unwilling to invest in a place where the loyalty is in question.
Fear of Losing Peace

Most men are ready to appreciate peace and stableness by the age of 40s. They are scared of entrusting a person who may come to mar their peaceful lives, which they had strived to restore. Passion is worth less than peace.
Trust Takes Longer Now

Men in their 40s don’t fall fast. They are more observant, test consistent and slow moving. This is no failure to take interest–it is self-defense, the result of experience.