It sounds like a pretty common form of rebellion. I once knew a man who would not change his socks, until they rotted off his feet, simply because changing socks was expected of him. Once he overcame the resistance and started changing his socks, he kept up with it, but he had to jump that hurdle of "don't tell me what to do" first.
There is the story of a young college student who had the scruffiest, ugliest beard on campus. Every day people would tell him it looked disgusting, and that he should shave it off, but he stubbornly refused. Suddenly he showed up for classes completely clean-shaven, not a whisker in sight. Everyone complimented him on how good he looked, and someone asked what made him finally shave off that ugly beard. "I did it," said the young man, "because yesterday nobody told me to."
And I remember, growing up in a fairly large family with only one bathroom, how I used to stay in there longer, the more my siblings pounded on the door and told me to hurry up. I was finished. I just stayed in there out of spite. The same principle contributed, I'm sure, to my sleep disorder. The more I heard, "You're going to sleep your life away," or "It's about time you got up," or "

Omigosh, she's AWAKE!" the longer I stayed in bed. Mostly because I didn't want to come out of my room and be confronted with the sarcasm.
In addition, I hate being told what I already know, or asked to do a chore I was just on my way to do. I used to respond with, "Well, I was going to do that, but since you told me to, now I won't." I realize this is not the healthiest way to respond, but it is quite common. In the book "Feeling Good: the New Mood Therapy," Dr. David Burns suggests, "Yes, mother, I have in fact decided to get out of bed in spite of the fact that you keep telling me to."
If I have a suggestion, easier to say than to do, it would be: Keep reminding yourself that you are CHOOSING to do what *you feel* needs to be done. You're not doing it because they expect it, but because you yourself made the decision.