My mom had some serious denial about my dad's abilities as his health declined. And he was just the type of guy to go along with everything to make her happy (hmm....cripes...that might turn into an A-HA thread for me one day...)
Luckily, we were able to share our concerns with the nurses and THEY could lay out what he should and shouldn't be doing. Mom would listen to them, not us...including my sister, the nurse...