I’m free now that my wife has gone to her hometown.
I have freedom because my wife has gone to her hometown
My wife has gone to her parents, so I am free to do anything I want
自由 - am free, have freedom
自由がある - I am free, I have freedom
自由があるから何でもできる - i can do anything because I’m free
実家はhometownかparents house。どっちでも使えるけどparents houseの方がいいと思います。実家帰る時両親の家に泊まるからparents houseがいい。
~~ので~~ because ~~ , since ~~, due to ~~
Because I’m hungry, I’ll eat my lunch
お腹空いてるのでランチ食べます
Due to the weather being bad, the soccer match will be cancelled
天気悪いのでサッカーの試合は中止します
妻が実家に帰るので自由だ
Because my wife has gone to her parents house, I have freedom
My wife is going back to her hometown this weekend, so I'll be free as a bird.
この場合、次のような言い方ができますよ。
ーMy wife is going back to her hometown this weekend, so I'll be free as a bird.
「今週末妻が実家に帰るので、自由になる」
to be free as a bird で「行動に制限がない・自由気ままである」と言えます。
ご参考まで！
イギリス 
カナダ 
