Life is full of changes and fluctuations. It also has a fair amount of challenges for most people. This often leads to a period of "falling off" where the discipline we have had in the past eludes us for a while. Such is life...it happens to the best of us.
The best approach (in my opinion and experience) is to not beat yourself up for too long and to jump back in the driver's seat without guilt. Take time to analyze what distracted you in the first place. Let's face it, we live under a high level of stress dealing with finances, family/children, jobs, etc. We must work on identifying and then avoiding any emotional triggers that cause negative behavior. If you seek them out you will find them. Another way of dealing with this situation is to create a challenge for yourself to go to a higher level once you get back on your discipline. In terms of health, this can mean some a short interval of fasting or cleansing and then a return to a higher state of consuming. This is natural.
Overstand that life does not move in an absolutely linear fashion. Embrace and learn from the transitions and allow them to fuel your growth. No time to sit and pout. Get back in the game!!!