Trust like Respect should be earned.
After someone has "demonstrated" (Honesty and Integrity overtime) it is only natural believe what they tell you.
One major mistake a lot of people make is buying into the old "I'll trust anyone until they prove me wrong" mentality. That kind of thinking is a conman's dream!
Each of us is reponsible for looking out for ourselves. Trusting someone too quickly,ignoring that (tiny voice inside of us) or evidence to the contrary amounts to (self-inflicted pain). Each day we make "yes" and "no" decisions. Being humans we're bound to make mistakes from time to time. Hopefully we're able to learn from those mistakes. Ultimately it's not about "them" and what "they" did or said. We have no control over anyone but ourselves! It comes down to finding out why WE "trusted" them.