Apart from your wife who else has access to your computer? Right now there are several options; which include someone else accessing your wallet physically and sending your coins to their wallet or malware so you’d have to help us narrow it down, let’s start by you answering the question I asked initially, does anyone else aside from your wife know the password to your computer? And also how often do you use your system to access sites that may not be secure? There’s a possibility that the malware (if it was caused be one) might have been in your system for some time before they finally got activated and acts.