Viagra may not be the best choice here. It's great for women but that's if they are already in the mood. Which is not the case with your wife. If she want to turn it around in a hurry I suggest she tries a test cream on her thighs (just in case she gets hair there). If her problem is hormonal and she's quick tempered this could make it worse. But at least with the cream, if she does see a change in temper, she can stop and it goes away in a day or two.