anti-depressants frequently do effect libido. you may have a 2-prong problem there. emotional/trust issues, plus medication. she may need to talk to a doctor about finding a medication better suited to her. good luck.
and Zipperhead: tri-phasal (yeah, I dunno about the spelling either) is a type of pill, not a brand. Orthotricycline is an example of a tri-phasal pill. what that means is that over the 3 weeks when we don't have our periods, we take a different amount of hormone each week. thus, three phases, or tri-phasal.
The other kind of pill is mono-phasic which means it's the same level of hormones all 3 weeks. this's the kind that you can take em longer and skip your period and stuff. tri-phasic pills don't allow that.