Why do Martha fans, who seem to grip about sexism/racism/any-ism all the time, reduce their favorite female character down to whether or not a certain guy likes her *that way*? Is the only way that the Doctor can "appreciate" Martha by giving her some lovin? I don't get this attitude.

We don't. Not all of us. Not by a long shot. Mostly we just ask for him to show a little more gratitude for the shit she went through for him. If the Doctor had ever said something like, 'Gee, Martha, it must have sucked for you to trapped in 1913 for three months,' we'd have a lot less trouble with the show.