My husband has Alzheimer's, and I have cancer. We spent $500 a month on Uber rides until we found a $3 alternative.

Carol Colborn and her husband, William, pay $3 a ride for a paratransit service. Courtesy of Carol Colborn

This story is based on an interview with Carol Colborn, 77, a retired academic from Mesa, Arizona . It has been edited for length and clarity.

My husband, William, and I married in 2008 when I was 60, and he was 65.

We both retired and went on an amazing adventure together: RV-ing full time across North America for eight years.

We drove to every state in the US, every state in Mexico, and every province in Canada. Then we traveled the world, visiting 29 countries in total.

The trips stopped after William was diagnosed with Alzheimer's disease in 2018, so we're glad we built so many happy memories on the road.

He'd shown symptoms of the illness, mostly forgetfulness.…