You can never be certain
Certain as I can be... 99% sure at least.
If I did tell her, I have no worries she'd share anything socially or family wise, it would definitely remain between the two of us. TBH I think she would understand, even though she may or may not approve.
Several years ago I mentioned to her about seeing an advert for what sounded like an top tantric massage with ligham happy end etc... was Savanya of Canary Wharf, now long gone, and when I told her about it she actually said I should visit and enjoy it. I never did, but it kinda fills me with confidence that she would be more understanding than not if I ever did chose to tell now. I probably wouldn't say anything, at least for the foreseeable future, but that could possibly change.
For now I'll stay quiet and continue to enjoy my little secret.