Minor note:

If you could care less about something, you are implying that there the thing in question has some measureable degree of importance, however slim, in that it is possible for that degree of importance to lessen.

If, on the other hand, you couldn't care less, you are describing a situation in which the object of your disdain has sunk so low that it is impossible to imagine being able to have any less interest in it.

It's an important distinction. Thankyou.