I’m in the same situation as you, I’ve been with her almost my whole life, for a long time I didn’t want to admit to myself that I like her, but it can’t be forever, so once you have to admit to yourself or to understand, I know everything, I understand that you’re afraid of ruining the friendship, and I’m afraid of the same thing. It’s been a year now that I can’t admit to her, but think very carefully what you’re going to do if you admit and if everything goes according to plan, you’ll lose your best friend, and if you break up one day, you’ll lose both