This is all very apt. Astute attention to detail when it comes to all of the dimensions of her particular character flaws. She is manipulative but not necessarily good at manipulation. Deceitful, yet not necessarily very good at lying. I think that one of the reasons why Kendra hated her even before she knew that David was her husband is because she could see right through her. BPD personas like Kenra can be almost uncanny in their sense of perception. It is kind of a tool of survival for them because the level of abuse Kenra suffered in childhood probably made Anna's upbringing with her cold unfeeling father and her sexually inappropriate brothers look like a bugs bunny cartoon. BPD folks like Kendra need to be able to read people so that they can mold their shattered identity to the sort of person that particular person needs so that no one will notice that they are basically the equivalent of an alien walking around in a human suit pretending to be like any other earthling. Kendra had Anna clocked from the start.
As far as Anna's marriage to David, I continue to think that it is salvageable but not necessarily worth saving. Even if it is saved, he is still with her. Maybe not today, tomorrow, or next year she will run into a man who feeds her the supply she needs and she will eventually give him sex to keep the supply going if he seems to pull away or lose interest. Maybe if Chris understood her a little better he would use this tactic instead of his full-throttle approach. Her pathology isn't going to change, and she is only going to get more likely to cheat as she gets older and the attention she gets from men starts to drop off. If the marriage is to be saved, to my mind in will have to be because of Anna's malignant qualities and not despite them. Since the three paths seem to boil down to stubbornness, reluctance, and acceptance her path may be a little more static than we think. With this in mind, the only way for her to save her marriage may be to understand the extent to which she is being manipulated, get angered by this, and turn her narcissistic rage on the bad actors in her life. Basically turning the tables on them. Subjecting them to the same gaslighting, flattery, and manipulation that they have been using on her. She is clearly capable of it. Unfortunately, in real life people with Anna's pathology only do this to their partners.
At the end of the day, the only thing that can save this marriage and keep up its perfect facade is if David is left in ignorant bliss about who is wife really is and if his particular behavior continues to serve her narcissistic pathology to the point that she will basically go "Dark Anna" on all the antagonists. Because nobody is in David's corner. He is all alone and everybody wants to ruin his marriage. He cannot save it. She can, but the question is what she will have to become in order to do it? I don't think that the loyal path hopefuls will be pleased to see the depths she is capable of stooping to in order to beat Kendra and the crew at their own game.