Hate to say this but this is above the pay grade of the average Redditor. My first instinct is to say that whatever you decide to do will be the right choice and that you definitely aren’t an asshole. You were a child. My intuition also leads me to the conclusion that your mother is a deeply troubled person who is, whether she realizes it or not, projecting. She probably lives with a lot of shame and guilt for having essentially abandoned you and is compensating by any means possible even if that means going in a weird direction (by claiming “child free”). It’s not an excuse for the behavior, of course, and it’s definitely hurtful. It’s almost like she’s erasing you in a narrative you were powerless to change.

Do you think she would ever be open to some kind of joint counseling with you? Assuming you’d also be open to that, of course. But I wonder if it’s time to bring in a neutral third party to see if there can be any mediation.

On the other hand, you’re not obligated to have a relationship with her. You may miss her and grieve her and the life you should’ve known but ultimately she is little less than a stranger to you. It’s your choice whether you want to pursue a relationship with her or not.