Wow, that is seriously twisted. Thanks for sharing. I’m glad you see things as you do, about her being the failure that she was; you could have been brainwashed to actually believe how she’d have you believe, that it was somehow your fault and not all hers. Then again you probably wouldn’t have survived, and the fact that you have goes to prove that you really are strong as you say.
I think one explanation for the perceived change in your mother’s behavior might be that children start out quite flexible and unquestioning towards their parents, and only gradually start developing their own will and identity. It could be she never was any good in raising up a real person, so you only came in full contact with her deficiency as a parent once you began to manifest personality. When you are very small, you more readily accept anything a parent may force on you no matter how wrong it actually is. It’s only later that you begin to have a sense of entitlement and are more likely to pursue what you feel is right for you, which sets you on a collision course with the parent that can’t deal with a child that is a real person and not just a dummy.