Brokenone,
It is good you are going to see someone. Some here are very wounded by their mates cheating on them. I'm sure you have read some of their post. I for one can't and would never judge you and your actions. you are an adult and you made a choice. Did his wife find out? or was it more he chose to end things for other reasons? You and those woman who have been cheated on might be able to help each other. By talking about this.
by the way with a T he will explain how things work. You can tell him or her anything. They have herd it all and then some. be prepared it can be hard getting to the root of things.