You're on the right track: you're eating well, you're working out, you're staying hydrated, you're creating boundaries around your sleep schedule and then, "all of a sudden," you stop.
You start engaging what you call "sabotaging" behaviors: you're eating whatever you want, you're skipping workouts, you're consuming sugary drinks, and you're barely sleeping.
In case you're wondering what happened, you've exceeded your ceiling of abundance, your threshold of what you feel you "deserve."
During our formative years, our authority figures and role models teach us what we deserve—not verbally, experientially.
For instance, let's say you grew up with a workaholic father who could never seemingly make ends meet; the message you may have taken away was to work hard and don't thrive.
Of course, this father would even tell you to "do better than I did," but his generous advice lacks the substance necessary to undo years of witnessing and adopting his behavior.
For you to move beyond the ceiling created by this person, you'd have to in a sense, "betray" them.
From the Paleolithic era, we've been wired from a young age to stay "within the pale" and not exceed the tribe's standards, or you'd be excluded and vulnerable to danger.
It's worth mentioning; you're behaviors aren't sabotaging (which suggest intentionality), as much as they're protective, to numb the painful feelings (fear, shame, guilt, etc.) associated with moving beyond your threshold.
The only way to "raise the roof" is by way of focused inner work, dedicated to acknowledging and validating your pain, betraying the lessons you were taught and embracing the resistance of receiving health, wealth and happiness.
It's so important to not hate yourself for being imperfect, all behaviors are learned, and with effort, we can forge new ways of being.
"Shame corrodes the very part of us that believes we are capable of change." Brene Brown