So you answered and solved the question yourself in your last paragraph when you wrote the honest halacha that a wife is required min Hatorah to serve her husband her entire life while her father she is not required to but if she does it’s a merit for long life.
In regards to this topic it’s important when a wife has her husband and father together to serve at the same time. For the father to see the respect his daughter gives to her husband his son in law and he will not be hurt or insulted for keeping him waiting but proud that his daughter takes care of her husband so devoted full time