I believe in past lives on a spiritual level.
I also believe that people bond with each other through bred-in-the-bone recognition. Like if I am attuned with someone and dig deeper into our family trees, I sometimes find that their ancestors lived in the town next to mine or in the same region (i.e. Carpathian Mountains). Or that our grandparents worked together once. That kind of thing.
Most of the time I accept it, and don’t try to figure it out.
And remember, sometimes we just hit it off with someone ~ we really are meeting them for the first time! Fodder for future life run-ins!