Ginger, that's horrific. I really think they just can't live with themselves if they admit what they've done. I know H thinks of himself as a nice guy. Nice guys don't cheat on their wives. So it's a cognitive dissonance situation where he has to change his behavior or perceptions to not feel mental stress. It's easier to change perceptions - decide that this somehow had to happen, was out of his power (like H had to move OW in due to her financial situation) than to change the behavior because that would also include an admission of having done something wrong.
M 16 yrs, WH62, P54 3 adult blended kids EA 11/13, BD1 6/14 PA fall 14, BD2 2/15 Piecing 2015, BD3 12/15 Separated 4/16 WH moved OW in 5/16 Divorced 6/15/17