Those of us who deal with a disability, but have parents who have been fairly healthy have a unique problem. Our parents understand our need for assistance, but they hate to accept the fact that they need a little help. They hang on with great tenacity to those behaviors that they equate with independent living. As we have become the oldest living generation in our family we understand that every time you give up something you do let someone else do it for you, you move closer and closer to that point when you may require full-time assistance, and older people fight that.
It was just very difficult to convince my mother that using a wheelchair in the airport cost much less of a loss of independence than she would suffer if she slipped and broke a hip trying to hurry to her next connection. We are all hesitant to accept the potential risky consequences to hanging on to that false sense of independence.
Good luck, and if you find a new workable strategy I am confident that many of us would like to know how you managed.