YOU SAID:

we are a couple since last year, when we celebrated the turkey party

INTO JAPANESE

私たちは昨年、七面鳥のパーティーを祝ったとき以来のカップルです

BACK INTO ENGLISH

We've been a couple since last year when we celebrated a turkey party.

INTO JAPANESE

私たちは昨年七面鳥のパーティーを祝って以来、カップルになっています.

BACK INTO ENGLISH

We've been a couple ever since we celebrated a turkey party last year.

INTO JAPANESE

昨年七面鳥のパーティーを祝って以来、私たちはずっとカップルです.

BACK INTO ENGLISH

We've been a couple ever since we celebrated a turkey party last year.