Someone has asked me to be friends...

She has only 5 friends. I know 4 of them, but the 4 people are virtually unknown to each other..... 1-4...
My Common Friend Number;
1) A French dude I lived with for quite a while in 2000-2001, who is back in France, in surf marketing, and has 1,200 friends, and probably will be friends with anyone...
2) A Italian surfer who I have never met, with 2,000 friends, ditto, probably happy to be friends with anyone...
3) A motorbike mate from Sydney with 400 friends
4) A Hawaiian SUP dude, semi high profile, with 1200 friends.
5th) A bloke from Melbourne who I'm sure I don't know.... On further investigation, he is friends with a very long time dear friend of mine from High School, late 80's and early 90's, etc.....

She has only 5 friends. I know 4 of them, but those 4/5 people I know are from different time periods, different places, and different circles of friends.... Completely different circles....

I'm confused !! I don't know her.... But how can we both know this specific wide eclectic group of people....