I had a gf that I was with until recently that claimed to quite like cycling and walking (things I do a lot in a novice/social but regular sort of way). We went on two bike rides and one walk in the last year. She hated it when I went out on 2hr cycles on my own, especially in the winter some of it she was worried about some calamity happening and some just plain not understanding. I don't think these people necessarily don't like cycling/exercise but how it relates into ones relationship. I got dumped for someone dubbed a "fitness freak" and this leads me to conclude that there was some unknown reason why she didn't like cycling/walking with me.