Do you want her back because she chooses you or because she's talked into it by her mom, worried about her future, or hates eating cheese toast? Probably if you ask any newcomer they want their spouse back regardless of the reason. I don't think that guilt, fear of the unknown future, or lack of anything better is a long-term solution. Focus on you. Take Puppies advice and use the next three days to keep working on making your life as good as possible as though she's never coming back. She needs time.
You cannot be lonely if you like the person you're alone with. Dr. Wayne Dyer