Frankly I don't know why you assume she has cheated. "Bad judgement" as a euphemism could be anything from gambling, stealing, drug usage or practically any other vice you can think of. Any could destroy a marriage.
You have leapt to a conclusion here re infidelity and it clearly strikes a nerve in you.
I submit you are helping no one here, and in the process, making not even a single cogent point in this thread. I see no fellow NT's jumping to your rescue either. Oh, except for Costrin's gem: "INFP's suck".
And, if you had investigated the OP's other post, you would have noted where she mentions she has been diagnosed as bipolar and has stopped taking her meds. Maybe that has more to do with her post than any 4 letter combo of assumption you've offered up.