I actually assumed nothing of the sort.  I was merely trying to reconcile his wife's actions.  If she departed for the mainland when all was well, they why the later call to police?  If things with Mr. Bernhardt were not fine, then why leave him alone and fly off to the mainland?  All I can surmise is that she must have had very compelling reasons (such as a family emergency, which hasn't been revealed thus far) or that she made a mistake in judgment.  That Mr. Bernhardt was killed strongly suggests SOMETHING went wrong don't you think?

By the way, your presumption that I believed or thought Mr. Bernhardt suffered from a mental illness illustrates my point:  you cannot assume people will understand what you mean (especially if you're calling long distance - and even if it appears in black and white).