The behavior has not changed overtime. I read about "hoovering" and I now realize that's what she was trying to do: Apologies are not sincere, but for the purpose of keeping me or winning me back.

For example, prior to asking me for a favor, she apologizes in advance saying, "I'm sorry to bother you this late at night..." or "I don't want to become a burden to you but..."

...and then asks me for a difficult favor that she knows would interfere with my work and life. If I say it's going to be challenging for me to help, she usually keeps pushing, or guilt-trips...this is tricky since she occasionally initially says, "I understand" but brings it up months later making sarcastic comment about it to let me know she holds on to her offense when her request cannot be accommodated.

Someone who say the considerate words that she say above and mean it, would not do what she does.

I feel like I have to constantly and actively remind myself, "Be careful. Her fancy words and sweet demeaner are not real."