Eckhart Tolle explains how the pain-body, accumulated emotional pain that dominates your energy, takes over when you don't recognize it. Most people spot it in others but miss it in themselves. The moment you notice it arising, you create enough awareness to stop it from consuming you.
Chapters
The key to becoming free of the pain-body is to recognize it for what it is when it arises. Always easier to recognize in the other than— much easier than in yourself. So you are more likely to recognize it in your partner when it starts than in there. But the more important thing is to recognize it in yourself when the energy field comes and begins to take you over. By recognizing it, you disidentify from it. It doesn't— cannot take you over totally if you recognize it, because to recognize means there is an awareness there now. You're aware that this is in your energy field. If you're not aware that it's in your energy field, it becomes you. If you're aware, it's still there, but it hasn't taken you over completely.