Trust must be earned. One of the ways you earn the trust and respect of your future employer is to gain their confidence during the interview process. Your past experiences might look good on paper, but you will also need to be able to explain your accomplishments and back them up with facts. Giving detailed examples provides hard evidence that you are reliable with a solid work ethic. When someone challenges you by not trusting what you say to be true, it can be a bit unnerving, especially if it's someone you have known for a while and trusted. When you give your example here, think through what caused this person to distrust you. Did it have anything to do with your behavior or communication? Be sure you fully understand what happened. Your response is key! You may not have been able to prevent the person's distrust, but you can have an affect on the outcome!