Having gone over your thread my best guess, (and remember it is all a guess because the only person who knows possibly what she feels is your W herself), is that she hasn't found happiness with OM and she became jealous at the thought of you seeing other people.
It's one thing to go off with another person yourself, but for the S you left behind to move on is another thing entirely!!! I would think that made her stop in her tracks a bit and reassess the situation. She sounds as though she was expecting to still find you waiting if things didn't work out with her and the OM, and then she realised that was a luxury that was going to disappear.
All the things you said do indicate that she is moving back into the R. I would take it all at face value. Be honest in your communications. Tell her that she needs to be honest too and comunicate how she feels - she must tell you if things aren't making her happy too. Remember you need a fresh partnership where you both feel comfortable; don't fall back into old habits. You have no reason to hide anything. However, especially with your history of anger, be careful not to be accusing when discussing things with her. Do you think you can do that? If you give her things to read to prepare her regarding your feelings you can always explain to her that although she may feel that it was not an A because you had separated, in your mind it feels different, and you just wanted her to understand where YOU are coming from.
Would you be willing to go to some sort of C together? My H and I considered it but when we got to a certain point my therapist said he thought that it might be more harmful than helpful. He felt that my H and I had cleared up most of the issues that hah led to the A and that too much C might end up harming more than helping. I have continued to see my therapist, (for cognitive behavioural therapy), as it continues to help me look at myself and moderate my behaviour and the dynamics in the M, ( I have a habit of withdrawing emotionally from the R when I feel stressed).
It all sounds as though it is moving in the right direction.
Saffie me 46 H 46 M in 1986 D20,D18,S16,D13 H's A 01/05 to 07/06 H recommitted to M 07/06 renewed vows 09/06 Going from strength to strength