I think if you get to the point where you dread to ride then you are riding for the wrong reasons.
I ride mainly because I enjoy it, and what health benefits I get is just icing on the cake, and I don't have to force myself. My only goal I set for myself is to make time to ride everyday, even if it's just a few short laps around the neighborhood.
I don't care to compete but rather ride at my own pace, at whatever distance I feel like riding, and ultimately just to please myself.

http://www.bikeforums.net/showthread...njoy-Riding-Or