It is more blessed to give than to receive - - and, for people who love to share, the recipients don't always feel as comfortable ...
If you were my friend, I would want you to understand that I gave what I wanted to give because that is what I had to give and you had use for it.
And, <g> since I totally get what you are saying, I would think that a quilt for your friend from her mom's fabrics would be awesome and overwhelming.
Don't you dare! ruin the reunion with comparing and trying to stay even ...
My mother tells the story of when she was a young mom and needed a lot of help from her MIL (a horse accident). When my mom said to my grandmother:
I don't know how we will ever be able to repay you for all the wonderful things you have done for our family.
Grandmother responded: You can't! But, some day, you will be in a position to help someone else as you have been helped. The best payment for gifts is to know that you helped someone get to where they can help someone else. Pass it on.
(Considering the conversation took place more than sixty years ago - - long before "Pay it Forward" doing random acts of kindness, etc - - you can see that there has always been hearts in the world who understood sharing.)
As a knitting person, I can tell you that you can't ever pay me enough for the joy I get from the creative process of making knitted items (to gift to others) ... as a quilter, I know you understand that there is no way to quantify the $$$ of joy you get from creating quilts.
Your friend shared with you what she had to help you achieve what you wanted and need to do. I am pretty sure the fact that you had some yarn was a bonus to her - - I doubt she is tallying $ for $ ... I can't say it enough - - don't ruin her gift by "keeping score" .... just enjoy her largess and pass it on (and, as I said: If she were to get a quilt of nine patches - - nice and scrappy <g> - - she will be overwhelmed. I am SURE of it! ) <wave>