I know all about that. I mentioned my website to you in a previous reply. I started my site in 1996 at university and have kept it all this time. After joining steemit 6 years ago, I stopped updating it so often but kept. Now recently I decided I really should make the effort to keep it more up to date, so I've been expanding on Hive posts there and I've also updated some of my personal info on the website about page. Because I agree with you, it is a very useful thing to have.
But updating it is much harder.... I haven't touched the code for years so I kind of forget how to do that. My website theme is a child theme of a standard Wordpress theme. Last week I saw that that basic Wordpress theme had a new version so I updated it without thinking. Whoops. Seems like my child theme did something that doesn't agree with the new version, so it broke everything. Luckily I was able to figure out how to revert the changes in the Wordpress database, but that was a little stressful. Now I have to figure out how to update my child theme. Something to do later...
Oh no, I'm so sorry you broke the website! Although, it's incredible that you kept it all those years. I hope you end up with something even better than what you had before.
Thankfully, Squarespace doesn't require coding but it's still pretty difficult to maneuver some of the UI just is the antithesis of intuitive. I'm just taking my time and am trying not to get too disappointed if I can't get a lot done in one sitting. I wish you luck in getting that done!