Gwen - what you wrote was like you had been in my head and read my journal. You are not alone in feeling this way, the questioning of what did I do to cause this, I must have done something to cause this -
Until recently I took on the blame for the demise of my m, because after all, if I had made him happy he would not have left ...right ....WRONG.
Yes I played a part in it and looking back I see that I had become lost in my marriage, I had lost my individuality and became insular and lonely. My h said recently " we enabled each other" and we did, but what he highlighted was that it was not my fault, that he was equally to blame - even more so as for him his thoughts snowballed so he ran, when he should have stayed and done everything possible to mend whatever was broken for him - something he now regrets not doing.
No one knows what goes through a MLC'er head, they become irrational in their thoughts, things that they once found endearing they now find irritating, they dislike anything that reminds them of the "old" person they have become - everything must go to make way for the new them, the reinvented them and that includes their h/w - So Gwen, please try not to let this movie continue in your head, you are a good person who did not deserve this to happen to you, your h is the one who has lost out, one day he will wake up and realise that.
This is your life Gwen, you only have one go at it so make it count - don't let what your crazy h has done rule your thoughts, set them free along with him.