DM, I don't think you ever ask her if she is ready to work on the marriage. She left, she will let you know when and if it is time. I also don't think you can put a specific time period on DB. You will know when you are ready to move on without her.
I totally agree with you about wanted to see any positive steps. I am three months into seperation and haven't seen anything other than moving closer to a divorce. Everyone moves at a different speed. I thought I was ready to start dating, then had a bad day, and realized I am no where close to being ready.
Just keep working on yourself. In the end that is all we have.
We are three months into our separation as well, and last night I got the "never going to happen, never going to change my mind, I am happy" text.
BD: 8/20/2012 W Files: 8/23/2012 S: 8/25/2012 (I moved out) D Final: 3/5/2013