How do I prevent my households from meeting one another?

[Fashionsimm]

I currently have three households lets call them A,B, and C. So when I am playing with  household A, household B and C meet each other and they form relationships and I don't want that happening. Is there a way to keep all your households separate so they don't meet each other besides putting them in different towns? I was told that you can click the new game button whenever you want to make/play a new household but if I'm scared that if I do that my other saves will get deleted. So is there a way to keep your households separate from each other? I've seen people do it I just don't know how they do it.

Thanks in advance

[ClayMask]

I don't know of a way you can control the relationships of a household you're not currently playing at the time, and doubt it's doable.  If you do click new game in the future, it won't delete your old saves.  You will just have to go to the load icon to bring them up again, which you can find at the top of the main menu.  It looks like a floppy disk.

[dodi90]

Even in sims 3 you cannot control the progression that you want. The benefit of sims 3 is the story progression can be turned off completely while the option is currently missing (only option for aging and putting empty houses with sims are available). The game also will randomly put relationship or jobs on inactive household. I only switch household for like 1 game hour and when i switch back my sims is already lvl 10 in Comedy branch!

[ManiSims]

What you can try is to save your households and their current houses to the Gallery. Then open up a new game (as ClayMask said above, it won't delete your files) and using the Manage Worlds screen, download the household into the new world. (I'm not the best at explaining these things but I'm sure there are very informative threads here on the forum that explain how to add a household/lot from the Gallery into a new game.)
Then go back into the original game using the Load Saves (floppy disk icon at the top of the main menu) and delete your household from that world. This way your households are in different games and won't interact with each other.