“You need to trust me” and “I need proof” can leave two people talking past each other. A smaller conversation may be more useful: choose one ordinary commitment that both people understand and that can realistically be kept.
This is a communication exercise, not a treatment method or a guarantee that a relationship will recover. Safety, boundaries and professional support may need attention before any shared agreement is appropriate.
Choose an observable task
Instead of promising to “be more responsible,” someone might agree to confirm a planned family meal by a particular time. State what is being agreed, when it should happen and how to communicate if plans change. Keep the first agreement modest enough to fit real life.
Make it voluntary and mutual. One person may agree to send an update; the other may agree not to turn that update into an interrogation. Neither commitment should require disclosing private treatment conversations or surrendering all personal boundaries.
Plan for a missed commitment
Discuss the response while everyone is calm. A missed message can be acknowledged, explained where appropriate and followed by a practical repair. It should not automatically become evidence for every old disagreement.
Equally, repeated difficulty matters. If an arrangement keeps failing, review whether it is realistic and whether additional support is needed. Rewording the same impossible promise is unlikely to help.
At a short review, ask three questions: Was the agreement clear? Was it manageable? What should change next time? Keep the discussion about the agreed behaviour rather than claiming to measure someone’s entire recovery.
Where conversations become intimidating, coercive or unsafe, seek appropriate support rather than pushing through the exercise. Rebuilding trust does not mean removing every boundary. A small kept agreement is useful because it creates one understandable experience of reliability, leaving room for time, support and further decisions.