Fred, I wrote another freepers years ago that I believe SADO had left her parents and SR in HI and was in hiding. SR had a history of abuse as reported by other wives. That pattern is never reserved for just one wife. If she had gone to Seattle for safety, her parents probably knew where she was, but SR didn't. Note she didn't return to HI until after he left. Changing her name would be consistent with hiding from him.
Many abusive men threaten to hurt or take the child, another reason for her to stay hidden. It is also a good reason NOT to file for divorce and expose her location until years later. IMO her impending remarriage gave her an urgency to file but more importantly it established custody and insured that BO could not legally be taken from her.
Have first hand experience with the problem and the above scenario certainly fits the pattern of an abusive relationship.