It doesn't matter AT ALL. My H walked out because he was done. No OW, MLC?(I have no definition for MLC that doesn't include depression as a major component), probably situational depression. But mostly he was done with me and my depression and my anxiety and my being controlling. He didn't have the tools to deal with that because of his stuff but that didn't mean I didn't need to work on mine.
All that matters is you and your journey. Which you haven't really started on. You've been convincing yourself to do it, studying routes and gathering supplies. Set a start date and take that first step.
Why do you need to say anything to him on Monday?
Me 57/H 58 M36 S 2.5yrs R 12/13
Let me give up the need to know why things happen as they do. I will never know and constant wondering is constant suffering. Caroline Myss
