It's very easy to revert to old ways because it's familiar territory. It's a constant challenge to maintain focus on your goal especially when your journey becomes stale.
Constantly remind yourself what you're doing and why your doing it. Not to sound cliche, but one of the best things you can do when you feel that cloud of doubt come on is breath. Just breath. It won't rain forever.
Eventually you'll reach your destination and everything will make sense.