He owed it to the man he had injured to preserve entire secrecy.
"He told me of the sin which might affect my marrying him," said Rachel, "but the rest had nothing to do with me.

He was right not to speak of it.

If he had told me, and then a few days afterwards Lord Newhaven had committed suicide, he would know I should put two and two together, and who the woman was, and the secret would not have died with Lord Newhaven as it ought to do.

But if Hugh were the man who had to kill himself, he might have told me so without a breach of confidence, because then I should never have guessed who the others were.

If he were the man he could have told me, he certainly _would_ have told me, for it could have done no harm to any one.