If you don't survive your own body, your own daily habits, if you are the instigator of dissolution and the saboteur of your own life, then you'll be miserable. No question.
Learn to say no and mean it. Learn to put yourself first--that is, your health, well-being, and happiness.
Your honest self comes first.
Your money? Your power? Your physical appeal? Your having it or not having it?
Who cares? That isn't tangible or sustainable, and the rest of us trying out here find it a bloody nuisance (but we'll give you space, at least, to find your way--lots and lots of space...distance, really...).
Learn the difference. It could quite literally save your life. Or, at least, your relationships.