I'm really confused about my feelings now

I'm 30 years old, my ex is 25, he left me because he said his 3 years old daughter was going to live with him in his house with his mother, his mother's cousin and her family, oh and also the mother (his ex). According to what he said, he did that because she threatened to leave to other place and that he won't see his daughter, she doesn't even have his last name, matter of fact he wasn't even at her birth because he even thought she wasn't his daughter, because his ex cheated multiple times, only because the toddler looks like him is just then that he came to realize that she was his daughter, even though there's no DNA test. Well, he left me because he said he couldn't be with me the amount of time i deserved and he left me when I needed him, my cat of 17 years old just died and besides my whole household is toxic, i live only with my mother but she is toxic, like way too toxic , she hit me yesterday because I forgot to buy something and she believes I'm this piece of shit that do things on purpose, I'm not..she thinks I'm like her hex husband, he raised me and everything bad that happens she thinks is my fault. My ex was my rock, he was my support, he helped me with my bills, I thought he truly loved me because of his actions, when my cellphone was stolen he bought me a new one, he helped me a lot at my job, we work together but he still helped me and wanted me to succeed, he even taught me stuff that could get him into trouble, he was so different from all the previous emotionally abusive relationships I had, that i thought genuinely he was someone special. Now he is writing to me continuously, i went through no contact and he has reached out several times, when I ask him why, he says he wants to know about me, that just because he decided to spend time with his daughter I decided to cut him off , i told him no, because it was his choice, a lot of people has children from previous relationships and they can live a good life, and he decided to exclude me from it , i don't know what to do. I don't want to get back together with him, my life is too chaotic for that, but at the same time I want him to regret what he has done to me...but I also miss my rock and my support..