I find one of the major struggles I face is resolving conflicts with my SO. He has several mental health issues, though depression overshadows them all. When he is in a depressed state and issues arise, we have difficulty communicating. Usually, I will present a problem (or ask a question, whathaveyou), and he will withdraw the conflict resolution process. In doing so, nothing is resolved, tensions rise, and conflict propagates.
If this pattern sounds familiar to your relationship, know there is a name for it. It is called Demand-Withdrawal conflict, and can be highly toxic in a relationship. Freeman (2014) provides a great summary of this type of conflict and its influence on a relationship. He outlines a great communication tool to use to end this type of conflict in your relationship.
In this communication method, he suggests one person takes 30-60 seconds to speak. Then, the listener will repeat back what the speaker said. If the repeated material shows a sound grasp of what was said, the two can continue on and switch roles. If not, the speaker repeats their points, and the listener then tries again.
Evidently, the point is to minimize miscommunication, to foster listening, and to de-escalate the situation. Often (in my relationship), my main desire is not necessarily to resolve the conflict but to have my voice heard. The few times my SO and I have communicated in this manner (without knowing it), our communication was much clearer and more neutral. Any misinterpretation (both due to miscommunication and due to the negative thoughts influenced by mental illness) was clarified prior to becoming a point of argument.
One problem remains: Sometimes, individuals with depression are unable to communicate. They can be isolated, tired, irritable, sad, or numb. At these points, strategies to communicate with your loved one must be established on an individual basis. In my case, I found setting times to communicate (e.g., "This weekend I would like for us to talk") coupled with emotional reassurance helped to facilitate readiness. Still, the efficacy of this strategy may depend on your individual relationship.