Ahhhh Yesssss...
For example I was dating this really hot chick but she kind of regarded me as "low priority". Of course I had other chicks as well and one in particular, "old reliable" was ALWAYS available. Physically she was hot but she was dumb as shit and could single handedly make me limp by opening her mouth (that is for talking).
Anyway, this odd arrangement went on for a couple of years (college days), she would come over at the crack of a whip and blow me on the spot.. Eventually I got so tired of her I started having "headaches" when she visited and didn't even want to fuck her anymore..
Well, years later I had another hottie that I just got tired of - she was a doctors wife and would gladly come to my office, pick me up and blow/fuck me or whatever I liked. I treated her like shit overall and really got bored with this quickly...