Trust is the essence of a strong mutual bond. Everyone has their own perception of trust. It is difficult to understand and estimate it. The sanctity of a relationship can be easily compromised if there is slightest of breach in trust.
It is not a constant, it is a random variable. The value keeps changing with each action. The action could be the slightest of change in the whole equation.
Trust is also not a bank account where one keeps getting interest on it once it is earned and deposited. The Principal has to be maintained otherwise it keeps fluctuating.
It is like hard earned income, very hard to earn but easily spent or lost if one is not handling it judiciously. One needs to earn it, save it, invest in it, cherish it and finally enjoy it.