As you already pointed out to TheOtherDave, we have multiple values which can conflict with each other. Maximally fulfilling one value can lead to low utility as it creates negative utility according to other values. I have a general desire to fulfill the utility functions of others, but sometimes this creates negative utility according to my other values.

Simply put, could you value X+Y (where the addition sign refers to adding the first event to the second in a sequence), but not Y?

Unless I'm misunderstanding you, yes. Y could have zero or negative utility, the positive utility of X could be great enough that the addition of the two would have positive overall utility.