I have written about this before, children learn about the world and their place in it based on their own little world. When that is short-circuited, it’s a struggle to relearn it as an adult:
All children learn about the larger world by extrapolating from the little world they grew up in, that of their immediate household and extended family. If you grow up in a place where you are loved and protected, feel confident to explore and take risks, and believe that others think well of you, the chances are good that you’ll see the larger world as one filled with opportunities to connect and make your mark. Even if you experience something untoward or unexpected, you’re more likely to be resilient and to see what happened as anomalous and be able to learn from it. (That is how a person with a secure style of attachment sees the world.)
But the child who grows up in a household where bullying, verbal abuse, and scapegoating are part of the everyday forms a very different vision of the world. The child who’s ignored has a different take on the world of relationship than the one who’s been taunted for her sensitivity or neediness. Again, these mental modes are unconscious and function as sieves through which experience is poured and understood. An unloved child who’s been under siege—mocked, marginalized, or scapegoated—defends herself by armoring and detaching from her feelings. An unloved child starved for love and attention remains open but ever vigilant for signs of rejection.
However, it is also not impossible to learn it later on in life. A struggle, yes, but not impossible.