I can't believe that I'm actually asking the question. I don't recall ever actually dropping anyone...
Here's the situation: I commute daily but am what I consider to be uber-slow at an average of about 13 mph. My husband is far faster than I, but diabetic thus needs the exercise, but can only ride on the weekends. We have a friend, husband of friend to be exact, that likes to ride with us. The trouble is, the slower we go so that he can keep up, the slower he goes. If we let him set the pace, we'll go about 7mph.
My frustration with this is... when I'm riding with someone faster than me, I keep "pedal to the metal" at all times. I push myself harder so that I don't slow down the other riders. This friend of ours doesn't do that--he does, in fact, the opposite!
After repeated discussions with them about the importance of exercise for type two diabetics, we gave up and dropped them on the last ride (new years day). Now we haven't heard from them since and they stopped showing up for the LBS ride on Saturdays too.
I keep telling myself that we did the right thing. My question for input of more experienced riders: what do y'all do? Do you drop your friends?