Hi Jenai - The only advice I can come up with is to plan ahead. You know what they say "Failing to plan is planning to fail!". Plan to pass up temptation, plan healthy snacks and pack them up well in advance before you're rushing out the door. Also, don't be too hard on yourself. We all have moments of weakness. Don't let those moments derail you! Think about your goals, leave the moment of weakness behind and keep moving forward.
If you are persistent, you will reach your goal. If you are consistent, you will keep it.