I feel so alone

My marriage is pretty much over and he has been controlling, emotionally abusive etc and his family I have been treated like dirt for years. I didn't have a good childhood and no family apart from my mum and she can be toxic even though she stepped up when I need help and support when son was born under emergency GA she helped look after me after. I don't have great friendships, I have some mum friends but nobody to count on or confide in, I used to think my husband was my best friend and I could tell him anything but I have been proven wrong and can't trust him at all. I don't have a job car or family I can't stay with and I don't know what to do or where to start my life, it will just be me and my son, I'm scared he will be alone and lonely like me, anyone else started over and life got better or words of advice? I am only here because of my son, because I know there is no-one else to take care of him and he keeps me going, he is the light of my dark life and I want to change and better but I don't feel like I belong or have "my people" I'm lonely, I don't want to be sad.