At the worst, there was one mitigating factor in it all.

He had no need to think of her.
Whatever the ruin and disaster that faced him in the next few hours, she in any case was safe.

There was no clew to HER identity in the letter; and where he, for months on end, with even more to work upon, had failed at every turn to trace her, there was little fear that any one else would have any better success.

She was safe.

As for himself--that was different.