I think it sounds like a BAD idea to get another dog. Your girlfriend isn't living with you, so no matter how much she may help with the dogs when she's around, she really doesn't grasp how much a third dog would make things more difficult. And as much as they belong to both of you, presently YOU are their primary caregiver. Until that changes, I'd be telling her she doesn't have a choice. I agree with pretty much everything else that's been said in this thread. Bad, bad, bad.