I too had a problem like this. I told her that I was very humbled that she felt that way about me, however, I just needed a friend, to talk and walk with. No more, no less. In my case, she said that's o.k.
We have been married for 35 years. She told me that you need to be friends before you can be lovers. In your case, you don't want to hurt her feelings and I understand that. Just be as kind as you can and tell her how you feel.
I hope you can be friends. We all need all the friends wwe can get.
Ken Reed Sr