Die a thousand deaths

"Die a thousand deaths" was one of an expression I used in my writing and the editors suggested me to have it edited out.

Ended up, the salad words outta my disordered mouth had been used before by Mr. Hemingway himself in A Farewell to Arms.

"The coward dies a thousand deaths, the brave but once."
"Of course. Who said it?"
"I don't know."
"He was probably a coward," she said. "He knew a great deal about cowards but nothing about the brave. The brave dies perhaps two thousand deaths if he's intelligent. He simply doesn't mention them."

Does Hemingway really believe that "the coward dies a thousand deaths, the brave but once" or "the coward dies a thousand deaths, the brave two thousand deaths"? Since I didn't read through the whole book, can't tell ya.

At least, here it is ... the context where the saying came from.