I know what you're saying. What next? How could I have been so (dumb, blind, foolish, etc., etc.)?
I can only offer what I keep telling myself; a bunch of cliches, but true for me.
--One day at a time. Where I think something is going or how it will turn out is hardly ever accurate, especially when other people are involved.
--Don't throw out the baby with the bathwater. I once cut all contact with a group of friends because two of them were "bad influences" on me. I regretted that for a long time, because of the good friends I lost.
--Don't burn bridges. Sometimes the only way onward is back across that bridge.
About your wife, I know people like her. In fact, my sister is like her. Nothing ever changed her mind, until recently. She has realized that according to her beliefs, her own "choices" must be responsible for problems she is having, including some health problems. The shoe is truly on the other foot now and she wonders why people have little sympathy and understanding for her.
Interestingly, this sister has always been the one to completely fall apart in an emergency or crisis situation. Just the phone being out of order can put her into a ranting fit that becomes an attack on anyone in the vicinity. Is your wife like that too?
I know for a fact that she is terribly insecure. She will hardly ever ask for help with anything, and then complains that no one offers help. If she does ask, she will then criticize the quality, amount, effort, or timeliness of the help given. She is compulsive with respect to cleaning and record keeping.
Any of this sound familiar?
I'm not really recommending this, but if the occassion for a rational discussion should happen, you might ask her what I asked my sister once. "Why do you choose to be so critical? Why do you choose to never give the benefit of the doubt? Why do you choose to never show compassion or understanding?"
My sister had no answers, but she did think about it, and her behavior did change for a while.
Don't know if a lot of this applies, but at the very least, maybe you can let her know that it is her choice to behave and think the way she does, and you would really like to understand that choice. Or is it a choice? Maybe it too is the result of a "sick mind"?
If you understand everything, some things are just as they are. If you understand nothing, things are still just as they are.