What an intensive emotional workout. You have been able to realize, I guess, that your mom did pretty much the best she could--given the context of "facts" on which she developed her beliefs.
Of course it matters, it matters enormously. The mother--daughter bond is designed in nature to be a basis of our trust & support system. Without that, the rest of our lives never quite "fit" snuggly. I know--from similar mom issues.
Accept the gift, and rejoice that your mom and aunt are still alive. You are strong and wise & inclined to forgive ... you may find much healing yet, the three of you together.
Roadie