The bottom line is togetherness: you' re living together.
Learn to be considerate, to accommodate your daughter-in-law' s change
of attitude. She has become quiet around the house, maybe, out of
stress from work or fatigue.
Learn to be objective, to ask yourself if you are overtaxing her strength
and if you are treating her like your own.
Learn to be kinder, gentler with her. Tell the Buddhist inside you to do
so. You be the one to effect changes first.