Divider would probably be fine. It sounds like the males wanted to mate and she is being harassed, they can be harassed to death. Now your female may still need a day or two to settle after divider being put up.3 males 1 female. I know,completely wrong ratio. I plan on replacing 1 or 2 males for females during the weekend. I'm definitely trying to fix that problem. Do you recommend using the divider until then? She'll be in the same tank but the other fish won't be able to get to her side.