If a person somehow loses the associated good feelings, ice cream also ceases to be desirable. I still don't see the difference between Monday and Tuesday.

I think I might have some idea what you mean about masochists not liking pain. Let me tell a different story, and you can tell me whether you agree...

Masochists like pain, but only in very specific environments, such as roleplaying fantasies. Within that environment, masochists like pain because of how it affects the overall experience of the fantasy. Outside that environment, masochists are just as pain-averse as the rest of the world.

Does that story jibe with your understanding?