It's so easy to get into a slump, to stop pushing yourself and just coast. This happens often because we forget why we do something. Habits are great, but sometimes you need to revisit what the purpose is of those habits.
You start to lose focus when your unclear on your reason for doing something. When you start to give yourself permission to slack off, to not concentrate so well, to not work as hard, then it's way too easy to continue that way. It becomes very difficult to get yourself back to where you were with routines, schedules and hard work. So keep in mind why you have developed these habits, and that will make it easier to stick with your resolutions.