Sorry you find yourself in this situation, but like your friends, my advice is also to let go. For one, he's already married. To suggest doing anything would be like giving the OW advice on how to break up a marriage.
So, somehow getting him back would be a cure for what ails you? Let's say that you woke up tomorrow and he was standing at your doorstep begging to have you back. Would the problems that ruined the first marriage be gone? Would you trust him? I just think you really need to consider that things won't just be magical. Take him down from the pedestal. Your life is passing you by while he lives his in the way he chose. I'm really sorry for you, but there also comes a time where we each have to accept that it's over.
In the end, it's not the years in your life that count. It's the life in your years. Abraham Lincoln
It is hard to fail, but it is worse never to have tried to succeed. Theodore Roosevelt
