history: I have a coworker always disturbing me during working to talk to me about subject that I am not interesting in.  I have a coworker always disturbing me during working to talk to me about subject that I am not interesting in. Oh that's frustrating_comma_ have you told them how you felt?
current: No, I am too shy to do that. This coworker start endless conversation and keep talking and talking. It is delaying me in work.
next: Oh that's too bad, I wonder if you could find a way to politely say something so you can focus.