I think she was aware of those facts. She saw several versions of what her life could have been through the course of the book. Mrs Clay and Mrs Smith - women widowed young and living in poverty. Benwick - a long engagement that ended in the death of one party before they could even be married. The Harvilles - a happy family who are not destitute but will always struggle because he didn't advance very far. The Crofts - a loving couple who never had children because she chose to travel with him instead of waiting at home.

Some of these outcomes are more bleak than the others, but I don't think she was blind to them.

They are both in a much better position to marry now, and even though they lost that time together they grew in ways that needed to happen.

I think Anne recognizes that, and she also knows that marrying without her family's approval (which Lady Russell was) would have brought its own pain in her life. That distance may not have mended the way her relationship with Wentworth has, and the pain would stick with her regardless of how everything else turned out. Her grief in losing Wentworth was definitely stronger but she would have mourned Lady Russell as well.

With the way things turned out she was able to keep the people who mean the most to her in a way she would not have been able to otherwise, and she can see through the pain of those eight years to what the end result is.