Complicated
Answer: Bunny, you sound like a nice person yourself. I'm sure you would not want to be responsible for destroying a good marriage. Suppose you were married to this man and some other woman decided she should be married to him? Now you said it yourself: if he is unhappy with his marriage. The only possible chance I see of this working out as you wish is if the man's marriage is already in trouble. If he is already considering divorce or has already filed for a divorce, then you may be in a position to "step in" when the time is right (assuming that he is not getting a divorce for another woman). Men are normally extremely secretive about such things at the office. But there ought to be some way of finding out the real state of his marriage. If it is sound, then you need to find someone else. I know that love cannot be turned on and off like a water faucet. But you have kept your feelings in check thus far. It would probably be best for everyone if you could find a single man to love. Good luck.