One of my best friends is an elderly woman who lives alone and cannot walk. She slurs her speech because of a bad head injury a few years back. She has a terrib

One of my best friends is an elderly woman who lives alone and cannot walk. She slurs her speech because of a bad head injury a few years back. She has a terrible short term memory. She is pretty cool. I visit her about three times a week and we will talk for hours. I wonder why we get along so darn well - I'm a 40 year old single guy with practically zero in common with her - but I always leave her house feeling happy. She will wave goodbye to me from the screen door until I am out of view. I like watching out for her wellbeing and brightening her day, yet I still feel I'm the one who is benefiting.