If she is willing to improve her libido, there are some things that can be used. Her diminished desire may also be related to self esteem issues in addition to the medication's side effects.
Women that use supplements with androgen properties report an increase in their libido. Some popular ones are : Tribulus, Macuna pruriens and pregnenolone.
Hypnotherapy is also a helpful tool to address this issue.
Boost Your Sex Drive - Binaural Beat Brainwave Subliminal Systems by Binaural Beat Brainwave Subliminal Systems
Sensual Woman - Hypnosis For Sexuality - 2cd Set (Hypnosis For Sexuality - 2cd Set) by Wendi Friesen (Audio CD)