Accepting money

A close family friend is super generous, and anytime we are together, she insists upon paying for the meal, activity, transportation, etc. Growing up, she was like a second mother to me, and she truly is one of the most genuine and loving people I know. However, I am now in my mid thirties, married with a child, and I feel uncomfortable accepting her monetary gifts. She mailed me a large amount of money saying that she wanted to cover my dress expense for her daughters wedding in which I am reading a chosen passage. She also cited my daughter's first birthday next month as a reason for the gift of "mad money." I'm not sure which is more offensive, to accept the money as a grown woman or to return it. I certainly appreciate her kindness and don't want to hurt her feelings.

Thank you for any help!