Quick, I need ideas... my boyfriend always gives me the phone and says here talk to this person... NOOO!!!?

my boyfriend and his friend talk a lot.. and his girlfriend wants to talk a lot.. but I really don't always feel that enthused ... any ideas... I said I was in the middle of something (which I was just online sending condolences to a friend whose grandparent just died) .. but still I don't know what to tell him! arrggggghhh!