Are you more affected by the farting itself or the giggling? My response to you was simply to make note that I find your advice to be conflicting and explained why. Ever heard of women taking a shit during labor? Original post cannot be on the front page or within 48 hours. That's really the only way. I've been with my partner for 6 years now and she is everything I've ever wanted in a partner. Not full on sharts, but like a mist.
A change in diet or position could help a lot.
Embarrassing Questions: Is It Normal to Fart During Sex?
If her reaction is still to say that it's unavoidable rather than looking for a resolution - but NOT an immediate resolution obviously - then they should break up. Maybe you have carpet burn or you just slipped in the shower or you sprained your wrist fisting your girlfriend. If not then it might be a pelvic floor issue. It is a rather girlish noise not like the wet windy fart which I imagine fat wives have. She's tried diet changes - lower fiber, cutting out all dairy, etc. Besides, farts are easy to laugh at because they are funny.