Here is what I found from the internet
I found that quote here on the internet (and nowhere else) but I don't really trust it -- it's someone's description, summary, interpretation, explanation of Buddhism.
There's a Buddhist canon i.e. the original Buddhist texts, which you can read for yourself (translated). Some of my earliest questions on this site were about that, and a lot or most of the questions on this site are about that canon.
But now I'll mostly link to Wikipedia articles instead of to the canon!
Does self-sabotaging instincts come from the ego?
I don't think so.
What I think -- though I've never been taught nor studied psychology -- is that the "ego" was a term invented by Freud, and that Freud was a 19th century quack (or a more charitably, a "pioneer"). He didn't invent the word of course, it's the Latin word for "I" the first-person pronoun, but maybe the first to apply it that way.
Have you heard of medieval medical theory, Humorism? It's nonsense to talk to a modern doctor about "humours", it's the wrong vocabulary and the wrong state of mind, the wrong theories. To me the word "ego" is a word in search of something to refer to -- "the word 'ego' exists so there must be such a thing as 'ego' or 'an ego'" -- but not a useful word.
This theory of mine is based on what I've read of the Pali suttas (which I'll explain in more detail soon, below). But there are other forms or schools of Buddhism, perhaps more modern, and I've read other people on this site write about "ego" as if it's an entity which tries to continue (hence "ego-defence"), and I'm not saying they're wrong (see also the parable of the blind men and the elephant), and they do say to beware of ego-driven behaviours.
What I do read in Buddhism is a lot of analysis:
There's a lot more than only "analysis" in the suttas, but there is a lot of analysis -- by which I mean identifying (lists of) things-which-exist, phenomena, dhammas.
Curiously none of these so far as I know correspond exactly to the modern word "ego" which I why I say that Buddhism does not describe "self-sabotaging instincts" as "coming from the ego".
I don't even know what "self-sabotaging" means in this context. I guess it means "action or non-action which isn't in your best interest" and quite probably "something which you judge to be 'harmful' but you do it anyway".
There are many behaviours that might fit this description:
- Smoking cigarettes and other addictions
- Being angry with people
- Procrastination in your duties (including "displacement behaviours")
The "three poisons" is maybe the most basic description:
- Ignorance (don't understand what's good for you, misjudge things)
- Greed (wanting some short-term pleasure)
- Aversion (avoiding some short-term discomfort)
There are other descriptions, like "the five hindrances" linked above -- of the kleshas/kilesas.
Kleshas, in Buddhism, are mental states that cloud the mind and manifest in unwholesome actions. Kleshas include states of mind such as anxiety, fear, anger, jealousy, desire, depression, etc. Contemporary translators use a variety of English words to translate the term kleshas, such as: afflictions, defilements, destructive emotions, disturbing emotions, negative emotions, mind poisons, and neuroses.
In the contemporary Mahayana and Theravada Buddhist traditions, the three kleshas of ignorance, attachment, and aversion are identified as the root or source of all other kleshas. These are referred to as the three poisons in the Mahayana tradition, or as the three unwholesome roots in the Theravada tradition.
There's a lot of talk about "the self" or "non-self" in Buddhism, which may be related to "ego". One of the first is the Anatta-lakkhana Sutta which I understand to be saying, "the idea of 'self', for example 'this is me' or 'this is mine', is not a useful idea".
See also A thicket of wrong views which I think implies that the idea of self isn't useful -- doesn't help to solve problems, isn't an actionable explanation of phenomena, is a useless theory.
how to break free from this cycle
I don't understand the specific question.
The general answer is probably, "the noble eightfold way" (and "the four noble truths which precede that") -- possibly starting with "right view", or possibly starting with "virtue" of the Threefold training.
The Kimatha Sutta (AN 11.1) identifies "skilful virtues" as fundamental, the bases.
I have heard that on one occasion the Blessed One was staying near Savatthi in Jeta's Grove, Anathapindika's monastery. Then Ven. Ananda went to the Blessed One and on arrival, having bowed down to him, sat to one side. As he was sitting there he said to the Blessed One: "What is the purpose of skillful virtues? What is their reward?"
Skillful virtues have freedom from remorse as their purpose, Ananda, and freedom from remorse as their reward."
"And what is [etc]