Pretended not to see a coworker

I once pretended not to know my old dental hygienist, who had cleaned my teeth for 9 years, because I didn't feel like talking. She came up like "Hey J! How are you?" And I said "excuse me?" She said "it's me,_____" and I just stared at her. She goes "...I clean your teeth...??" I said "You must have me confused with someone else" and walked away. My next appointent she brought it up and I said "oh...yeah.....I must not have recognized you without your mask on" She looked at me really funny for a minute, then started gabbing away like always lol

Like when I go out to have a smoke from work so I can have some alone time and tech on my phone but then someone else comes out too to chat.. ugh