You don't need to defend her or her choices to anyone. They were hers to make.
Your relationship is over and anything from here on out is speculation. Do not waste time speculating on what might have been or what was or what wasn't.
Now is the time for what is
What are the lessons you learned? what can you take away from this?
if you didn't learn a lesson, you will be doomed to repeat the same scenario over and over
