The difference is whether the relationship is working or not. A working relationship is one in which the needs of both partners are being met. If it is not working, then the people in the relationship resort to coping behaviors rather than real communication. Stonewalling is coping behavior. The person doing the stonewalling feels too broken emotionally to participate in a difficult conversation.
The first step towards repairing a non-working relationship is to get on the same page about whose needs aren’t being met, which needs those are, and an agreement to work towards them. Lots of times both partners are feeling unfulfilled. It can come down to one partner having to “be the bigger person” and work harder for awhile than the other person. As you can imagine that doesn’t happen very often.
For example, if someone feels like you aren’t contributing enough to keeping the house clean, orderly and maintained, forcing them to do it, the stress of the additional work plus the feeling that you are causing the problem will eventually wear them to the point to where every interaction starts to become a fight.
If fights continue with no resolution, then the relationship almost completely breaks down, attempts to communicate are met with no attempt to even engage. That’s stonewalling.
The answer is to build conflict resolution into the relationship, so it never gets to the point where you’re really fighting. If these are present, and each partner feels like they can be relied on, then little spats never grow to threaten the relationship.
This is ideally done really early on in the relationship, in the ‘getting to know you’ stage. You recognize little aspects of the other person and develop little techniques to route around the trigger points. The lady I’m with gets pretty triggered when she feels her country of origin is being maligned.
If I were just an idiot about it and kept pressing her over her ‘silly’ patriotism, then our relationship would start breaking down over the trigger point. She’d stop wanting to be with me, and we’d eventually stop talking.