These are hard relationships. There can be good times, yes, and then the hard times are pretty difficult -- not only physically or in terms of energy, but emotionally it can wound, and the wounds can be hard to get over.
The whiplash can also be difficult. Like you're saying, one day can be pretty good, then overnight, everything changes... but for how long, hard to know.
I'm curious, for background, how long have the two of you been married? Has this pattern been going on for a while, or did it start recently? And do you have any kids?
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I thought I would use the time to do some more research and self-help of living with a BPD person (she is not diagnosed but checks many of the boxes).
Makes sense that even if she's not diagnosed, the traits and behaviors are what's challenging, not the label or lack thereof. My husband's kids' mom has many traits but no diagnosis (that I've heard of), and the fact that she isn't diagnosed doesn't make interactions easier.
What resources have you found in your research so far?
We do have a
book review section that has a lot of reputable titles -- worth a look.
In terms of other support/resources, do either you or your W have a counselor/therapist?
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Feel free to share more... we'll be here.
kells76