I think humans' greatest problem is not communicating enough.
Look at it this way, why can't she just go straight to her bf, and
tell her that she's disappointed he seems not to know her well
enough? I personally feel that sometimes, while friends and people
here can be well-meaning and give advice, in the end, we are not
your friend or her bf. They two should sort it out themselves. Coz
we can say somethings, and if ur friend take it the wrong way, it
could cause further misunderstanding, and maybe even the break-up
of a couple.