The Agony Of Breaking Apart

Oh ! the agony of people splitting up, jealousy and rage! Someone close to me, which has to remain nameless, is going through all of this agony. He and his wife were only together for three years. Things were fine, up until the time that she decided to start snooping into his past. Why? Why all of a sudden, does the past make a difference? To me, the past is gone. There was nothing for her to find. He had already told her of his past. She accepted him and married him. So, why did the legal paperwork make a difference? Why would anyone feel the need to snoop just for the sake of snooping? At some point, did she NOT feel secure? As sad as this all is, I happen to know both parties involved very well. He gave her NO reason to snoop. He felt violated, but got past it, until it happened over and over again, and not only that, she started fighting with him over things long gone. They eventually broke up because she was so jealous over his past, that she couldn't stop arguing over things. Why the mistrust?  Again, a mystery. They had spent nearly 24/7 together because he worked from home and she didn't work at all...I mean, she didn't even keep her house up.  He did it all, supported her and what became of this?  Maybe they should have spent more time together before getting married?  Who knows, but it seems to be happening all the time these days...you hear it on the radio, you see it reported on the news...people breaking apart. What happened to the good ole days of staying together?  All I can say, is thank goodness there were no kids in the marriage.