Assalamualaikum. I wanna ask something, how not to hate your own sibling who really made a big mistake that affecting people around her especially our family? I feel really mad at her because she's really made a really huge mistake and also she had misused the trust that we put on her, like my family really trusted her but then a whole thing is a lie. I'm really sad seeing my parents lose their appetite and sleep. I really can't see her face right now but she's my sibling.
Alaikumassalam wa rahmatullah,
How you feel is a natural human reaction to that situation. Islam does not expect you to stop being human, it only expects you to keep your impulses under check and to do what you know to be right and kind whether you feel like it or not (to the best of your ability). Just give it time and maybe you will start to feel better toward her, especially if she works to regain your love and trust. If she approaches you and asks to be forgiven and be given another chance, then the pious and admirable thing to do is to accept it and go along with it even if you are still too upset to consider forgiving her.
You may also be interested in this previous answer, it is about parents but it somewhat applies to siblings too: Is it sinful in Islam to not love your parent?
Best wishes.