I'm glad that there IS a diagnosis and so the vets know what they are treating. Now it is a matter of working out the medicating to make it the least stressful you can. Hopefully with it becoming routine she will start to just accept it. Do you have the liquid gabapentin compounded to a flavor that masks the taste? Is your vet consulting a neurology specialist... I remember years ago having a rescue cat that was put on a seizure medication to treat this and that worked...so maybe there are other options if the gabapentin ceases to work as well?