I'm so sorry about your breakup. I don't think anyone deserves to be left that way. Especially after 10 years. You are right, that is no way to treat anybody.
I see u have a plan to move forward with your life, and that's great. But sometimes we just have to grieve a little bit. Yes...it hurts. But better to get it over with then ignore it and have it plaque us later in in life. It's hard when we don't get any explanation or reason when another person treats us badly. I think it makes you over think every little detail...trying to find the answers.
The answers may be there...if u think about the last year of your relationship. Were there things she mentioned more then once? I find that most problems in a relationship have been fought over numerous times...because we don't resolve them properly the first 20 times!
Anyways. I wanted you to know that I feel for you. I would be angry if I was in your situation as well. I hope you find peace as you move forward. Take care