I don't want a boyfriend who doesn't treat me well.
I don't want to continue in a relationship with a man who doesn't value me as a person.
この場合、次のような言い方ができますよ。
ーI don't want a boyfriend who doesn't treat me well.
「私のことを大切にしてくれない彼氏はいらない」
to treat someone well で「人を大切にする」
ーI don't want to continue in a relationship with a man who doesn't value me as a person.
「私を人として大切にしてくれない男性とは関係を続けたくない」
a man who doesn't value me as a person で「私を人として大切にしない男性」
ご参考まで！
カナダ 
