The basis of trustworthiness is saying what one means, and meaning what one says. Trust is established when follow-through with one's promises happens in a timely and excellent manner. Trust can only flourish in the absence of lies and deceptions. Almost all of these conditions for trust are likely demolished when addictions take over one's life.
Family members who are trying to rebuild trust with a recovering addict are not starting from scratch, but are trying to climb out of a deep well of hurt, disappointment, and fear. Rebuilding trust involves commitments from family members as well as the addict. Family members must commit to being honest with their feelings and their expectations. They must be clear on boundaries.
The addict must commit to honesty and truthfulness regardless of the fallout. He must not only remain sober from his addictions, but also begin to make amends to people he's hurt with his addictions.
The fear of being hurt again must be dealt with if trust is to be re-established. One must be realistic, but not fearful. Whether an addict or not, future mistakes are inevitable. However, future mistakes cannot be handled now. Avoiding trust because of fear of future hurts will prevent healing in relationships.
Family members and the addict must all be committed to taking down the defensive shields that were a hallmark of interaction during the height of the addiction. If slips or relapses occur, the addict must be honest with family members and allow them to see her steps to return to recovery. Start small.
In rebuilding trust, it's better to make a small promise or commitment and keep it, rather than to make large promises that are impossible to manage. Genuinely focusing on the needs of others, paying attention to their feelings, and spending time and energy on building them up goes a long way in rebuilding trust.