Created Neighborhood on Sims 2 ALWAYS Deletes?

So I've been playing the Sims 2 for years! I've been having this problem ever since I got the game, but would always shrug my shoulders and restart everything. But now I want it to stop! Ok, after taking the Sims 2 games off my computer and loading them back on. I would go to create my own neighborhood and my own people and have a great start for quite a few months. Now I have the Sims people without aging so I can have fun with them longer. But after awhile (and I mean almost a year), I'll load the game up and my neighborhood and people disappear! I had no computer problems or fail loadings with this game to make it do this. Now I went to many different help sites and I got many answers. One that was quite popular, but didn't work was to right click neighborhood file on the Sims 2 file and restore. Or reloading the game, or copy and uninstall your game, load it and paste it in. But keep in mind that since this was create, it won't come back by doing this. So what do I do?