Most people particularly with PDs like NPD or even BPD will never be 'diagnosed'
They usually think their fine it's everyone else who's the problem.

If the op thinks the caps fits it probably does.

I don't need a 'expert' to tell me my mother was NPD. I lived with her!
She ticks the boxes.
But then therapy is not widespread in UK wereas in USA it seems commonplace.

I would definitely not travel to your sister or get on my knees and beg.
Offer an olive branch if you want but no begging. I've found begging will just get you treated like dirt.
She sounds like a difficult person.

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