You do not owe anyone an explanation. The only thing that matters is that you did what was best for you and your family. If you are a loving mom who cares about her children and they are fed then really that is all that matters.
In the long run, all the wonderful memories is what your children are going to look back on . That has a huge impact on their lives. Formula feeding can't change that.
Just be the best mom you can be is all
Oh this is teal_phoenix btw