Does she want me back?

Hi All

I split up from my girlfriend of 7 years last January 2016. Since then ive got on with my life, but if im honest I have missed her, but it was clear she didn't miss me. I have still been in touch on occasions to see how her daughter is (12) as I was in her life for 7 years and loved her like my own.
I sent them both Christmas cards and gave her daughter a presents for Christmas. But other than that I haven't seen either of them for months.
Then out of the blue I texted her to see how her daughter was and she replied saying that she missed me massively, had thoughts loads about getting back together but obviously was wary about it going wrong again. The long and the short of why we broke up was I was going through major issues in my life some of which I hadn't resolved for years. As a consequence our sex life suffered for months. But she couldn't take the rejection any longer. I completely understood and said I would get help. But this was too late for her and we mutually split up. There was no shouting etc, it was a calm split.
Since then in the last 10-12 months ive had counselling and changed my life around for the better. And yes I would love her back, but I don't know how she feels. That was until the text a week ago. So I have written her a letter explaining how I feel and what I would love to happen. But I have also mentioned in the letter that Im not going to put any pressure on her. I still love her, and if anything I love her even more now. I realise I let her down, but I wasn't myself. I cant change what happened before, only going forward.
So my questions is why did she mention that she misses me and that she had thought loads of times about getting back together? Apart from the letter I sent I don't know what to do next. I could ask to meet with her in person, but as she said she has been avoiding me for a reason she hasn't explained, I don't know what else to do.
Anyone have any ideas what I should do next?