This is nothing new. I have seen many times when some chick would marry some guy for status and have a partner on a side. Some of them do it because they can control the guy so bad. Some of them get married because they fear that her age is coming up for marriage. Also you have to be very naive to think everything will get better. When you get older with her, she would find some younger guy to please her on regular basis. As you may notice, this kind of behaviour does not come at age of 40... It was in her blood ever since...
My advise would be:
I would first man up and face the facts.
Eliminate any risk by dumping her.
Also I would not look down on Scarborough while at the same time moving up north. If you can fetch some serious cash, Scarborough has its jewls. It is just the media propaganda that make it look so bad. This is done for the reasons to cover up crime rate in Western part of Toronto. It all comes from our mayors and other big fish that have all the strings in their hands. Trust me.