How to handle your wife walking out suddenly?

If you are still in love with your wife, start by asking yourself if putting the 'suddenly' in that question was really fair... And work on it. Try to understand if there's something you can do to get things right, and put a plan in action. On the contrary, if you want to put the past behind you, get yourself new interests in your life - new hobbies, new friends, maybe a new job. What you can't do is feel sorry for yourself, or sit and wait for things to change.