According to Professor Bernard Roth at Stanford, swapping one word for another could make all the difference in how you approach your goals.
The next time you say "I have to" in your mind, change "have" to "want". It’s a very effective exercise in getting people to realize that what they do in their lives — even the things they find unpleasant — are in fact what they have chosen. It allows you to realize that you might really want to do the unwanted chore because the benefit of doing it outweighs the discomfort of doing it.