YOU SAID:

I can't wait until my girlfriend gets back home from vacation.

INTO JAPANESE

彼女が休暇から帰ってくるまで待ちきれません。

BACK INTO ENGLISH

I can't wait until she comes back from vacation.

INTO JAPANESE

彼女が休暇から戻ってくるまで待ちきれません。

BACK INTO ENGLISH

I can't wait until she comes back from vacation.