It's so great that your DD has the insight at that age to understand her feelings, and so great that she feels free to share them with you, lillamy.
My mother kicked my dad out when I was 12, and he died when I was 18, and although he hadn't been in my life for six years, I was totally devastated, and I know it's because I felt robbed of a dad who could have been a great dad. But I was so grateful to my mother for having had the courage to give us a stable life without him.
Your family's doing great... it's painful, but you guys are there for each other, which is awesome.