My wife was fine with me playing MMO's until I met another woman online and had an affair with her. Now she hates MMO's and me for a long time. I can't say that I blame her.
It was the worst mistake I have ever made in my life. I am not proud of it, at all. And I'm so lucky my wife is still my wife. I have tried very hard to make amends, but you can never ever truly do that. It eats at you every day of your life.
I've learned my lesson and solo play this one mostly. And not much more then 60 minutes a day if that.
Take my advise, if you love your wife but find yourself falling into a situation with someone else online or in R/L, run away. It is best to remove that situation from your life, because no matter how much you may think you can control it, that is just an illusion. You can't.