Ultimately, parents are people and some people will always prioritize their own needs. But yes- there have been situations where I've questioned where my Dad's priorities and loyalties truly lied. He pretty much exposed me to (likely) narcissistic abuse and, took their side at times. That was pretty revealing. The whole- knowing which side your bread is buttered.
I think love has many forms and some of them aren't all together healthy. I think we can love an idea of a person. What they represent. We may love the idea of the love we have for them. But ultimately, it doesn't always stand up to testing.
I'm sometimes astounded by how much parents do for their children. They move to be closer to them- to help out with grandchildren etc. They remortgage their property to help them in business ventures. My parents moved 100's of miles in the opposite direction and tried to present it as them doing us a favour- we won't become a burden on you.
That said, they're by no means terrible either. In many ways, they are actually very good parents. But sure- there have been times in life, I've realised I'm on my own- no matter what they pretend to say.
I imagine it's a form of love that made her angry at your CTB attempts. A selfish form I suppose- that she would likely feel devastated to lose you so- she perhaps became angry at you for trying to make that happen. I think love can (unfortunately) become very possessive- rather than be a genuine concern for someone.
Her response seems like a typical 'tough love' response that I would also sometimes get. Not necessarily because they don't care but- because they may genuinely think it's what we need. I suspect there's frustration there because- probably their parents gave them the same and presumably- they complied so- why don't we? Maybe the whole: 'I can't help you if you won't help yourself'. Which is maybe only partly true if we are truly debilitated and need more support.
It does sound as if she expected you to support her emotionally- from a young age- which never seems fair to me- for children to have to effectively parent their parents.
But then, most people don't enjoy being criticized. If you were pointing out her shortcomings, it sounds like she retaliated with that. Which we should be more mature not to do as adults but, we're not always that either!