Get her on Bio-HRT. It'll literally turn her around 180 degrees. NOT conventional HRT!!! You need a doctor who will prescribe bioidentical HRT. At this point she probably will just get progesterone and testosterone but that is enough to stop the hot flashes and turn her libido back on (and straighten out her sleep, and fix the aches and pains, and give her energy and stamina ... the list of perimenopausal symptoms is horrifically long, 32 symptoms and I got most of them so I'm telling you, it can potentially ruin a woman's life and she doesn't need to live with it!).
To repeat: She does not have to live with this, if she doesn't want to. But FYI -- Some women are actually happy when they can delete sex from the equation (I wasn't, I got suicidal) just saying ... and the whole breast cancer/heart disease thing, yeah that came from a study using "conventional" hormones inappropriately dosed to women who were LOOOOOONNNNG past perimenopause. Doctors who know what they're doing catch women in the perimenopausal phase and start trying to balance things out long before true menopause takes place.