I’m an engineer. Writing by hand I would always use a fraction. If I had to write this in an email or something (quickly and informally) either the context would have to be there for someone to know which one I meant or I would use brackets. I certainly wouldn’t just wrote 1/2x and expect you to know which one I meant with no additional context or brackets

Hi there - I am also immunocompromised and have 2 exciting autoimmune diseases. I work in an office every day (actually a lab, but regardless).

Your behaviour is not normal, and you should seek therapy so you can enjoy your life!