Constantly threatened to leave me, then flip when I get tired and stop begging her to stay

as the title says. my wife who is a pwBPD has constantly threatened to leave me at least once a month for the past 2 years. she never missed a chance to dig up old issues to remind me of how im not doimg good enough for her, and that what I do is the bare minimum (i disagree but I know now that its pointless to argue that when shes splitting).

she would set traps to see "if I love her". especially on days where in busy with something or on days that I have something planned for me, tho rhe latter isn't as common. but I swear I feel like whenever im occupied with anything she will feel threatened and start doing things to test if I would do x or y.. sometimes I can react and give her some reassurances, but sometimes. I really cant.

anyways, we got to a point where I was fed up, tired of doing so much effort, yet everything is forgotten all of a sudden when shes not feeling well for any reason. sometimes she'd be upset over a completely irrelevant thing g to us or our relationship, and while venting aboht that, it turns into telling me how little I care aboht her. so i told her caplmly and explicitly. I am not longer going to ask or beg you to stay or give me other chances. I love you anx care about you, I do effort, and I have constantly tried to fit your definition of care and love without you noticing. it seems like I am incapable of loving you how you want to be loved, and it is dragging both of us down. I wont ask you of anything, if you want to stay and work, stay, if you feel like im still not living or caring about you, then lets save ourselves a long useless conversation that will only repeat.

well, she threw a big tantrum, cried, had literal physical complications which I wouldn't get into too much details. the next day, shes a different person. she acknowledges I love her, and that I do care for her I just don't show it well enough and that she needs to work on that. im kinda relieved, but cautions.

few weeks pass, another argument. she starts her usual rant and I take a deep breath and before I can say anything, she starts backtracking, and changes her tone instantly.

this happened a couple of times afterwards, and it seems like something switched in her brain, I dont know what it is or what happened? but she hasnt said a word about divorcing, taking a break, or leaving me for almost 2 months now. we have small arguments, but its never the hopeless Rollercoaster anymore, just a short angry spurs and it seems like she is more aware kf things.

what are your thoughts? has any one experienced anything similar?