Well ... I do not think its just Catholics, many Christians in general pick and choose what they want and apply what they will. The more I learn the more I realize I have done/do the same and its something I continue to look at and try to get better with.
MLCrs will do as they will do, unfortunately this just takes time for them to complete the journey and there is no guarantee at the end of it ... but then again there never was, we all just assumed the happily/ happily enough ever after.
As far as the fast track to D ... yeah ... mine did the same, then let it sit, then was hell bent again .. then let it sit ... back and forth she went till now, I do not think its much more than trying to see if this is finally the way to happiness, or possibly with all that has happened she simply feels there is no return, to much scorched earth to try to fix ... maybe both or none of the above ... really impossible to know what is going on with them especially in my case now where there is little to no contact. Her lawyer asked me how I felt .. calmly I told her that if she felt this was the path to her peace and happiness then I want that for her, I was sincere and meant it .... throughout all this keep in mind as painful it is to be the LBS ... being the MLCr is much much worse, one day I do believe most of the MLCrs will wake up at some point and that realization of "My God what have I done" will not be an easy thing to face for any of them.