Trust is a foundational ingredient of any healthy relationship. Maybe because of this foundational quality, people tend to think of trust as an aspirational state of unwavering robustness, when in reality, trust is messy. It will be put to the test, most of the time in unintended ways. Then, if your expectations ebb too much on the side of this unwavering robustness, you will quickly find yourself in a state where you don't trust anybody and deprive yourself of human connection and authenticity.

Perhaps the target state for trust is an antifragile system? For the sake of definition:

"Some things benefit from shocks; they thrive and grow when exposed to volatility, randomness, disorder, and stressors and love adventure, risk, and uncertainty. Yet, in spite of the ubiquity of the phenomenon, there is no word for the exact opposite of fragile. Let us call it antifragile. Antifragility is beyond resilience or robustness. The resilient resists shocks and stays the same; the antifragile gets better."

—Nassim Nicholas Taleb

It's unlikely one will build trust through volatility, randomness, disorder and stressors. Probably the opposite will work better to build it. You also don't want to inflict such phenomena on any relationship intentionally. However, it is naive to think it is avoidable.

With trust established, genuinely trustworthy relationships get stronger and better in the face of unexpected adversity. Therefore, trust is antifragile.