Answer:
Reward herself for sticking to her goals.
Step-by-step explanation:
When you are trying to stick to a habit, you want to make sure that you aren't hurting yourself in the process. Increasing sugar intake is bad for you, isolating yourself is also bad for your mental health, and so on. Rewarding yourself makes your brain learn to do that action to get more rewards, like if you are training a dog to sit and give it treats when it does it properly.