Thanks for this, LC! The other thread was turning sour, sometimes a new thread can refresh things nicely.
My replies to your question in the other thread were not offensive, that I'm aware of, so I'm going to recap here...
Estrangement, IMO, is a very painful thing. Then again, if a relationship is painful, in itself, I imagine estrangement can be very freeing for one or more parties to the conflict. Granted, I don't think it should be done lightly. Efforts should be made to talk things through. Since mismatched expectations are often involved, I think those need to be explored. Boundaries may need to be set, in some cases, and others may need to find a way to accept them. If one person tends to make offensive comments, etc. the other may have to call them out on it and let them know how they feel about it. Apologies may need to be made and forgiveness given, if possible. If, unfortunately, nothing works, contact may need to be cut back to decrease chances of friction. Only when efforts to fix the relationship have been tried - and failed - do I think estrangement is in order.
I get N & G's feeling that a CO should occur only in the event of a "heinous crime," such as abuse. However, I would say that should be the only reason for an IMMEDIATE CO. At the same time, I can see a CO happening if non-criminal, non-abusive offenses are committed over and over, despite requests for them to stop. This includes the infamous "death by a thousand paper cuts." A steady stream of nasty acts and comments, no matter how minor, can, no doubt, drive some people to estrangement.