What does it mean when you dream about cutting your dog in half to make her fit in the car better?

In this dream, the "dog" symbolizes something else that the dreamer is trying to "fit into" her/his life. The car represents the dreamer's present circumstances or perhaps the dreamer's schedule. The car also could represent "getting somewhere" in the sense of getting ahead in life. The dreamer wants to include the thing represented by the dog, and so is considering going "halfway"

• for example, that might mean taking half of a course of college

classes, or perhaps going back to work part time instead of full time.