Calories is watching fat intake with food. if you're trying to watch your calories yes it's the fat, because you are trying to eat less fat to maintain a good diet.
sugar crash is to much sugar intake and it makes you fatigue and go to sleep or you feel drowsy and lazy. To much sugar intake is a reason for sugar crash.
Do not follow self-destructive behaviors such as drinking, doing drugs, over or under eating. go to therapy or a physiologist, focus on positive self-talk and self-care. push negative people out of your life and be kind to others(it's very rewarding).
remember, paths can vary based off of mental illness that the person is suffering.
Living by your personal values sounds easy—at least in theory. Your values, after all, are simply the things that are important to you in life, so it should be natural to live by them.