I can understand why he wouldn't file for a divorce; that would require him to start paying child support and perhaps alimony.
The book mentioned in the above reply is called: This Is Not The Story You Think It Is, by Laura Munson.
Me: 45 WAW: 45 | M22 | T25 | No Kids Nov 09 W Filed | Dec 09 Separation Mar 17 2010 Divorce Papers Signed | Divorce Hearing Cancelled Moved back home May 2010 PA Confirmed June 2010 | W left Dec 7 2010