自我悔恨to regret one's actions

• 当你们看到这封自悔书时，我已经离开了这个世界。

  By the time you read this letter of regret, I will already have left this world.

• 我自悔自责，竟然一稿多投。

  I regret my actions and castigate myself for submitting one manuscript to multiple publishers.