Dear Ron
This situation is tricky, and I understand that you fear the loss of a friend. But I believe in 2 great outcomes for this situation: 1) you tell her how you’ve felt about her for the last years and you become a couple. 2) You tell her and she does not feel the same way – but you can stay friends. Yes, this will be painful, and yes, you will feel rejected if she doesn’t see you as a possible partner for an intimate relationship. But if you are truly great friends, with a little distance, you will be able to figure it out.
I would tell her, because life is so short and it is not often that we meet people who we truly connect with.
So I hope I could help.
All the best to you!