As a counter-point, you built this thing in part to give the world something good and uplifting. If you kill the child, you guarantee the outcome of failure.
Sure there's a chance that the person you pass it to goes in a direction you don't like, but there's also a chance it goes on to magnify it's mission. It's such a neat project and something I wish I'd discovered before today (sadlol).
Hell, maybe I'll take it over if you're willing. I'd keep you access to it and grant veto power over any changes you don't like. What's the current stack? LAMP or something else?
Have you considered making it into a software package?
You could take any custom code you wrote (like the layout of the pages) and make a guide on how to remake your site from scratch (what software packages you ran, OS, things like that) and post that to github as open source.
That would allow you to keep your baby but then let your electric grandchildren float off into the internet to see where they might sprout.
Another thing is if you decide to bury it, do not burn any bridges. A few years later you might want to restart it. So make notes, keep everything archived.
Hell, maybe I'll take it over if you're willing. I'd keep you access to it and grant veto power over any changes you don't like. What's the current stack? LAMP or something else?