Deeper down she is 100% reliant on my income and has never had a career to speak of, terrified of being outed to her family as a failure, terrified of becoming her mother who had an exit affair and is now on disability and a burden. Convinced that no one would be interested in her as anything other than a hookup. As for stability and support., I believe she sees me as the best she can get.
At the deepest level, I believe she is terrified of intimacy, filled with self-loathing to the extent that she believes no one including herself would ever love and accept her if she were truly vulnerable, and finds a shallow attachment the most comforting.
Sooooo... you are sure she won't leave you because she has no earning potential, her self-esteem is trash, and she's too terrified of her FOO? It seems, oddly enough, as if you are counting on this dysfunctional "nowhere else to go" blackmail, as if you see it working in your favor. So recap then:
She cheated.
She won't or can't change.
You find this totally unacceptable and feel no love for her.
But don't like how D looks.
So you decide to do without everything in life because it's safe.
And find twisted comfort in the belief that you hold all the cards over her life and ability to function.
Which feels fair and appropriate because you are pissed.
Two people trapped in a fake, toxic, dysfunctional union, stuck with each other in misery because they have no idea how to choose differently.
I recognize much of this in myself and see how we entered our marriage with dysfunction.
You could set some serious boundaries--telling people, living honestly, separating, seeking intensive help, finding self-esteem--and give her the chance to actually confront her demons, slay the dragon, and change? Or you two can continue to hide from your real issues until things blow up even worse. The choice seems obvious, but idk.