Perhaps Dave was under such mental anguish due to work/business...

Perhaps Dave was under such mental anguish due to work/business issues.
Perhaps Dave was behind in the mortgage or perhaps Dave was recently retrenched and too ashamed to tell anyone.
Perhaps Dave was so repressed due to being married to such an unreasonable, destructive and financially irresponsible wife that he found himself seeking solace in the arms of someone better .

Nah...wouldn't be any of that.
Dave is guilty. His wife said so...