I think it's time you stood up for yourself and broke it off. You don't need either one of them in your life. The dictator wife who will only allow you to be with her husband on her terms, never alone, unable to even talk or email him privately, and belittling you when you express your needs. And her ineffectual, weak husband who happened to get you off but does nothing else to treat you like someone who is cared about. You, always feeling dismissed, discarded, disrespected and inconsequential to both of them.
Who needs that bullshit? Time to let go of them and get yourself a life.
There are loving people out there with less issues -- or at least issues that won't damage your spirit or esteem -- who would welcome you into a relationship in a nurturing healthy and fulfilling way. But sometimes, those new doors won't open until you close the old ones.
Snap out of it!