You are asking a most provocative question of us. Well, exactly what is your question?
What is it you want? Do you want to see this man and live out this fantasy of long ago? If you do, it will be perilious, if not the end of your marriage, and maybe this other man's. Perhaps that is what you are longing for, the end of your present marriage. I think so.
My best friend is going through the exact same thing. She has a 11 yr old daughter, adored by both she and her husband. She saw an old flame in another state and boom, instant attraction. They had an affair. Her present husband has had a low sex drive that has been bordering non-existent for years. But the old flame was exciting, and that was the beginning of the demise of my friends marriage. It was really what she wanted all along, and used the affair to substantiate the whole business. Luckily the old flame is not married (he had 3 marriages to be exact...what a winner).
So....you could ruin both marriages, or you could just end your marriage. This is not a judgmental statement, it's a factual statement.
Honey, you are a very unhappy wife. You need to take care of business before you take any actions with someone else. I so feel for you..it sucks.