Hey! You acted better than I would have, so kudos for that. You know who ever said it only did because they were with friends and showing off. Gutless ***** like that have no balls when alone. Personally I would have stopped and dropped my bike and walked back wanting to know who has the big mouth I have to shut.
But I rage abit on my bike toward idiots, not smart I guess.
So, now remember what that idiot said, save it and the next time a hill gets tough, get pissed off. Everyday you are making progress regardless of the scale. Your body will get toner, leaner and more effecient and soon enough you will wonder why you only did 15 miles a day--not the 30 or 40 that you are soon to be doing. Be patient, and when you pass me on hills try to act like it hurts, even just a little.