When I was in grade school, I had a teacher that wreaked havoc on my future academic career. She instilled in me a fear of asking questions.
When I got up the nerve to ask her something she relished in making me feel stupid for not knowing the answer. "I went through this already. Everyone else seems to get it, why can't you?" It was as if me not knowing the answer reflected poorly on her teaching, and in order to avoid feeling like an inadequate teacher she made me feel like an inadequate student.
In addition to the snarky remarks I'd receive if I asked a question, she would often pick me to answer a question that I didn't have the answer to. The response was either the class laughing at me or her pointing out that I wasn't paying attention to her lesson. This teacher branded into me that I was slow, stupid, and a bad student. For the rest of my school days I avoided asking questions. Instead, I'd struggle through trying to get the right answer. I'd settle for lower marks when I could have done better simply by asking the teacher or my peers for help.
She, for whatever reason didn't like me (or rather didn't like herself and was taking it out on me) and rather than show patience for her "slow" student she decided to ingrain in me that anyone who didn't get it, anyone who needed help, anyone who was different was wrong or "bad."
By instilling a fear of being wrong in me she was keeping me from learning how to do things right.
Rather than ask, and save myself time, I fumbled over and over again to arrive at the same destination as everyone else. I figured out that she was doing a good job of keep me from progressing. I had become the person she wanted me to be, because I was too scared to be more.
This is how many oppressors work. They get you to feel like there is something is wrong with you, they make you a victim until they no longer have to tell you're not good enough; you'll say it yourself.
Long after I left that class I was still hearing "you're stupid" in my head. But it wasn't her voice. It was mine!
The odd thing is, meeting her and going through that was one of the best experiences of my life. It made me see how people can attempt to keep others down and in their place in order to gain power. It made me alert to it. When someone says "you're stupid" now, I think, "No, I'm not and I know exactly what you're doing."
The same applies to abuse. If someone hurts me the last thing I'll do is remain a victim of their hate. That's what they want me to do.
I can't erase the years where I sat passive in class and in my personal life not asking for help or asserting myself, but I can use the years I have left to learn from that experience and be a much better person.
Don't let an experience in your past harm your future. The best way to teach anyone who tries to keep you down a lesson is by standing up.