Procrastination is just a fancy word for avoidance.
Socially, it is acceptable to procrastinate. After all, everyone does it sometimes. This makes it easy to not even think about why you are procrastinating.
Conversely, it is not normally acceptable to avoid something or someone. It smacks of cowardice, and almost no one wants to be considered a coward.
Think about that when you know you are procrastinating on certain tasks. Ask yourself: What am I avoiding? What am I afraid of?