Unfortunately I can relate to this.Yeah, right. Wait til you have a pretty young sweet woman give you a big smile.
Then you realize she's not doing that as a come on.
It's because she is reminded of her grandpa.
Where I work a lot of college girls come in. Sometimes one will linger after the others have left and talk and flirt with me a little.
I figured out that at my age it is because they think I'm harmless.