Hi, I'd like to help you with your question.
It sounds like you were severely abused as a child. Your father and mother were cruel by working you so hard, hitting you, and demeaning you. And you mentioned sexual abuse as well.
There is no reason that you need to even continue contact with your parents. Many abused children feel guilt at the idea of cutting off contact with their parents, but if your parents are still abusive after all these years, you are not obligated as an adult to continue to accept the abuse. If you are near your parents or live with them, move out. Do not respond to them or contact them in any way. As long as they can abuse you, they will and you will not be able to heal from the abuse until you remove yourself from it.
You also do not have to listen to anyone else yell at you or demean you. Over the years, you have learned that you deserve being treated this way because you were taught that you were not worthwhile as a child. But that is far from the truth. You deserve to be treated with decency and respect, just like anyone else.
Learning that you are worthwhile and developing a self esteem does not occur overnight. It takes work and determination. But with the right help and some persistence on your part, you can do it.
Here are some resources to help you:
Adult Children of Abusive Parents: A Healing Program for Those Who Have Been Physically, Sexually, or Emotionally Abused by Steven Farmer
Toxic Parents: Overcoming Their Hurtful Legacy and Reclaiming Your Life by Susan Forward and Craig Buck
Healing Your Emotional Self: A Powerful Program to Help You Raise Your Self-Esteem, Quiet Your Inner Critic, and Overcome Your Shame by Beverly Engel
You can find these books on Amazon.com or your local library may have them for you.
I hope this has helped you,