Trying to be strong but my wife is leaving

My wife told me three weeks ago in therapy she wants a separation. I was shocked as earlier at dinner she was planning out Christmas gifts for my nieces and nephews we would be visiting this Christmas.

I am trying to be strong and we have worked out the rules for our separation. We will go to couples therapy and individual therapy. I am moving out to an apartment and we will have weekly "dates." The problem is that she wants to date other people because of her lack of "experience". I am the only person she has ever been with and because of her weight before me, she was too insecure to have intimate relationships with other people. 

Part of our problem is that we have a "Parent-Child Transactional relationship" based on my childhood trauma, depression and ADHD. Because of this when I get upset or stressed, I shut down and start lacking in my responsibilities at home. This causes my wife to stress because she takes over the responsibilities. I have been in therapy to address this and it was in this therapy she broke the news to me.

Last night in our first couples therapy she reveled that there was someone she had met months ago that she might consider dating now but did not pursue because we were working on things. I have loved and cared for her for nearly six years and even now, she is the only one I want. It kills me to think of her with anyone else but I understand that I haven't been the best to her because of my issues. I want her to be happy because I love her but I can't help to think that she will find someone better than me and any hope will be lost.

I have never met anyone like her and we compliment each other. She tells me that love and romance were never the issue with us, it was my shutting down and letting stuff in the house go.
I am being strong and respecting her space and moving out soon but I am afraid that she is separating with me not to work on our own self improvement but to make the end of our marriage easier for her. 

I don't know any help or advice is welcomed. I know I have to be patient but right now, I feel like I am in Bizzaro world.