Yes you both do need to be treated . she is right .do it at the same time it's not that big of a deal. It is different ,because you can develop it alone but you can pass it back a forth .I know it don't seem to make sense but the treatment will work and you will be fine.
Both of you should be treated with antibiotics at the same time. That way you will both get well at the same time.
Once you are finished with the course of antibiotics, you both should take acidophilus to replace the good bacteria in your gut.
Vitamin C will also keep you from getting this infection over and over again.
Hope this info. was helpful. Wishing you the best