Stay with your wife and, if you must, continue to have sex and think you are in love with the men you date. When you get old enough to be visibly unattractive and start being viewed with disgust and contempt by the younger ones whom you do fancy (can't be long now since you have already been married to your wife for 20 years and you must be already be around 50), you will be treated very badly indeed and be very very grateful that you still have a wife to go back to.
Do you have children? If so, you may risk losing them if one or some or all of them decide to have nothing more to do with you, or your relationship with them will suffer, if it becomes their view that you are nothing more than a silly self-indulgent man who has gravely injured their mother just so he can have sex with men.
Look upon being gay as just fancying someone else other than the person you are supposed to fancy - your spouse. Lots of heterosexual married men are in that position, as I am sure you already know.
Homosexuals are very nasty to other homosexuals they don't fancy, probably in the same way that women used to be nasty to each other before women's lib. You could get young flesh as an old queen, in theory, but only if you are very very rich. Not worth it, mate.