Wow, Pearl, I know how you feel. I'm not where you are, but W is showing signs of life. And big part of me is actually disappointed. When I was dark, and she wasn't making any attempt to see me, then it sucked, but I could focus on buttoning things up and moving on.
Then they do THIS crap - and you wonder if they are sincere, or if the OM/OW broke up with them, or if they are just feeling guilty, and if they come back, it'll fade.
As far as your situation, it's obvious that xBF made some pretty major concessions - admitted to being wrong - etc. I'm guessing there is a part of him that holds you partially responsible for the problems, so maybe he is fighting his pride a little too?
I used to think about what I did wrong in my R, and then I would remember what W did, and I would get a little miffed.
So, anyway, if it were me, and in my heart I still had room, I would say something like this:
"Dear xBF, I really appreciated your letter. I know that we have been through a lot, and it means a lot to me that you would be willing to share very deep feelings with me.
I am not sure how I feel at this point, but I do know that I am not willing to consider any possible reconciliation while you are still with OW.
Thanks, Me"
If my W wanted to reconcile, my first requirement would be: "Do not contact OM in any way, shape, or form ever again. If there is a single text, phone call, or visit, it is over, and I walk immediately, no looking back."
See what he says - if he is a typical WAB (WalkAwayBoyfriend) then my guess would be that OW knows nothing about the letter. I'm hoping that he would be more sincere/genuine than that, but let's err on the side of caution.
But, first things first: is there room for him still in your heart?
