index.html

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Construtor & Destrutor</title>
</head>
<body>
  <script>
    class minhaClasse {
      constructor(elemento) {
        this.elemento = elemento;
        this.elemento.addEventListener("click", this.acao);
      }
      acao() {
        document.getElementById("log").innerHTML += "</br> Clicado!";
      }
      destructor(elemento) {
        this.elemento.removeEventListener("click", this.acao);
      }
    }

    document.addEventListener("DOMContentLoaded", function(even) {
      var objeto = new minhaClasse(document.getElementById("botao"));
      document.getElementById("botao_2").addEventListener("click", function() {
        objeto.destructor();
        delete objeto;
      });
    });
  </script>
  <button id="botao">Adicionar</button>;
  <button id="botao_2">Deletar</button>;
  <div\ id="log"></div>
</body>
</html>