Never felt more lonely since ASD diagnosis

I was diagnosed a few weeks ago and initially I felt a huge wave of relief and burst into tears. Then I felt confusion and anxiety wondering if I will ever feel like I belong and wondering who I really am without the mask. And now I just feel so completely alone. I don't have many people in my life. Just my partner and children and my Mum. My Mum has always been unable to see things from other people's perspectives and is heavily critical of anything I do. But after having gone through the journey with me getting my own children diagnosed, I honestly thought she would be somewhat understanding when I got diagnosed myself. Instead she has been just the same as always and doesn't seem to understand that I really just struggle with life and have done for my entire life. I feel like if I try to take one step forward she is right there dragging me back three steps simply because she can't accept me for who I am. I think she thinks I can just snap out of it. I don't want to lose the only family I have around but I also don't want to keep being dragged back when I'm trying to progress. I have tried to talk to her but she is incredibly stubborn and can never accept that she is ever in the wrong. I just don't know what to do or who to turn to anymore. I feel so lost and lonely and I'm constantly worrying about what is going to happen in my future.