My iphone's apps are copied onto someone else's phone each time they sync
By default apps are copied to iTunes from the phone when syncing. By default apps are copied from iTunes to the phone when syncing. This can be annoying - personally it's my kids who put a thousand irritating games on their phone, but I can see that a husband would be just as bad.

Connect your phones to iTunes. Find them in the left-side menu, or drop-down.

Under the Apps menu you can turn off syncing.