Kissing goodbye on the lips is not a west coast thing, it is an expression of love for the ex, and contempt for her husband. For the wife to continue to kiss a former lover and now boss on the lips, after her husband has expressed his feelings about this, is not a 'West Coast" thing, but rather a woman with no respect for her husband, her marriage, or the ex's wife. For Prudie to use a throw-away line like "if they are doing this in public, you know they are not doing anything in private" is absolute crap.
The LW'ers wife and boss are continuing their relationship and displaying that in public. The LW'er needs to see a lawyer immediately and file for divorce. He should not be married to a woman with so little love, respect or loyalty to him.