The part you are ignoring is that she presented what her partner thought was a complete history when it wasn't. If she didn't want to be truthful then she should have just said that wasn't something she was comfortable discussing. As a personal rule I am open about my recent past (5 years or so) but anything beyond that isn't relevant to the relationship and I make that clear.
Doctor!
Specifically look into getting hormone levels tested And blood work done because those can tell what is wrong if something is
And make sure you have a healthy lifestyle
Low “bad” stress Healthy food Sleep Excercise Water Ect
But the test are the move
The part you are ignoring is that she presented what her partner thought was a complete history when it wasn't. If she didn't want to be truthful then she should have just said that wasn't something she was comfortable discussing. As a personal rule I am open about my recent past (5 years or so) but anything beyond that isn't relevant to the relationship and I make that clear.
How old are you and your best friend OP?