Hello February
Since your older female is in menagerie your other kitty will not find her to re-partner with her and this will break up their partnership automatically.
If you click for the menu of the male kitty, the "Info" button, you will see how many days their partnership will last.
If this is too long for your taste you can also buy a break up vita in the main store this also works with one kitty present.
I hope this helps :-)
