It’s a sad fact of life that not every kid gets the parents they need and deserve. I suspect that your parents keep putting you down because they are avoiding taking responsibility for the fact that their daughter was abused. It’s easier to blame you than to take ownership of what happened. Ideally, they should have been in family therapy at the time, not just you. The people who should have been feeling remorse were the adults involved!
That being said: Please give yourself enormous credit for what you’ve been able to achieve in spite of being abused. It speaks to an inner core of strength that not everyone is born with. You stopped self-harming. You did well enough in school to get to uni. Look in the mirror and give yourself a huge congratulations. Do consider going back to a counselor, not because you are “crazy” but because you deserve the support and guidance of a counselor to further process what happened to you now that you are older and can think about it with more sophistication.
What do you do now? Stop trying to change your parents. They have no motivation to change. As one of my teachers used to tell me: If you want to get out of a tug of war, drop your end of the rope! You have a life to live. You don’t need their approval. You don’t need to take in their criticism. Arguing with them doesn’t change them and only makes you feel worse.
I wish you didn’t have to live with them but that may be your only option for now. Change your reaction when they put you down. Simply say something like, “I’m sorry you feel that way” of “I’ll think about what your said”, Smile sweetly and go about your business.
If Covid is keeping you in the house, take as much distance as you can from them by finding something constructive to do with your time like doing advance reading for courses.
By all means, contribute to the household by doing such things as washing up dishes or doing the family laundry so there can be no legitimate complaints about your being there. Just quietly do chores that need doing. Don’t look for credit. Don’t be surprised if you never do them well enough. That’s to be expected.
I’m glad it is summer so you can possibly go outside for a time every day. Nature is a great healer. Being out in the fresh air and getting some exercise will help your mood.
I hope you get to go back to school in the fall. Do think hard about what kind of work you want to do eventually and how best to position yourself to do it. Consider internships as well as course work. Ideally you will get out on your own and can then limit contact with your parents to what is most tolerable for you.
I wish you well.