He won't listen to me because he doesn't want to hear what I have to say.
この場合、次のような言い方ができますよ。
ーHe won't hear the things he doesn't want to hear.
「彼は聞きたくないことは聞かない」
things he doesn't want to hear「彼が聞きたくないこと」
ーHe won't listen to me because he doesn't want to hear what I have to say.
「彼は私の言うことを聞きたくないから、聞かない」
ご参考まで！
Looks like I can't hear what I don't want to hear.
"聞きたくないことは聞こえないみたい"
- Looks like you can't hear what you don't want to hear.
夜中にトイレに起きるのがイヤとか眠りが浅い気がすると言う人に晩酌をやめてみたらと言ったけど聞こえないみたいだった。
- There's someone I know who doesn't like getting up in the middle of the night to use the bathroom and says that they don't sleep well. I told them to stop drinking at night but looks like they can't hear what they don't want to hear.
カナダ 
アメリカ合衆国 
