My Beloved Mother Has Passed Away

As-salamu alaykum everyone, I’m not sure how to begin, but I’m writing this with a very heavy heart, so please be gentle in your replies. I’ve lost my dear mother and I feel so lost. The sadness is overwhelming because no one around me truly understands. I’m still young, and most of the elders around me, in their 70s, still have their mothers. They try to comfort me by saying that everyone must return to Allah one day and share how they lost their fathers at an old age. But honestly, it’s just not the same. I’m young, my mother was young, so they don’t really get how different this grief feels. She won’t get to meet my children, her grandchildren, while others’ parents have lived to a ripe old age. My mother’s life was very difficult. She was married before, and tragically, one of her husbands caused the loss of her baby. My father was not a good man. She married him as a single mother, but he was abusive throughout her life. He physically hurt her, controlled her financially, and even committed acts that are hard to speak of. Until her last day, she lived under constant stress. Yet, somehow, she always showed love to us and kept a smile on her face. She suffered many health problems because of him, both physical and especially mental. He would just accuse her of being crazy and never admitted his wrongdoings. Others advised him to care for her and ensure she took her medication, but he never did. There’s much more to her story, too painful to share fully. She endured so much pain and hardship in one lifetime. Our home was also neglected; he never cared for it properly. I’m heartbroken that my mother had to live such a hard life, and I feel guilty. I wanted her to live so she could be with me in the future. It hurts that she was the one who left us, not him. My father seems unaffected. He behaves normally and even listens to music like nothing has happened. I want to keep my distance from him. He calls and acts like I’m being disrespectful for not answering. I don’t want to speak to him. She passed away because of his negligence. Is it okay for me to have little or no contact with him?