pour your heart out

自分の心の内を打ち明ける、本音[自分の胸の内]を打ち明ける[ぶちまける]

Ex

  • I poured my heart out to him and then he told all his friends what I’d said

Reference source

  • https://eow.alc.co.jp/search?q=pour+one%27s+heart+out+to
  • https://dictionary.cambridge.org/dictionary/english/pour-your-heart-out