YOU SAID:

i think i have feelings for my girlfriend's best friend

INTO JAPANESE

私は私のガールフレンドの親友の気持ちがあると思う

BACK INTO ENGLISH

I think that I feel like my girlfriend's best friend

INTO JAPANESE

私はガールフレンドの親友のように感じる

BACK INTO ENGLISH

I feel like a best friend of a girlfriend

INTO JAPANESE

私はガールフレンドの親友のように感じる

BACK INTO ENGLISH

I feel like a best friend of a girlfriend