NEVER say the word 'FAILURE'. It's so negative and so defeating. Say I got off track (even if it's for months), or I lost focus, or I am not ready to do this now, whatever works for you that leaves the door open to success. Just don't say I FAILED, please.
Even when you are not on track, or choose not to be on track try to keep a journal of some type.
Keep smarter foods in your house. Even if you are compelled to buy junk food try to buy healthier and keep trigger foods out entirely.