One English phrase that seems pertinent to the situation you describe comes from William E. Henley—better known (to me) as the co-author of the multivolume, turn-of-the-century magnum opus Slang and Its Analogues Past and Present. Henley's untitled poem number IV in "Life and Death (Echoes)" (1875), reprinted in A Book of Verses (1888) contains this quatrain:
In the fell clutch of circumstance / I have not winced or cried aloud, / Under the bludgeonings of chance / My head is bloody, but unbowed.
The idea here is that even in defeat a person may retain dignity and honor.
An Ngram chart tracking the frequency of occurrence in the Google Books database of publications of "bloody but unbowed" for the period 1880–2019 suggests that this shortened expression was virtually unknown before 1888, but reached its height of popularity (in published writing) in the mid-1940s, near the end of World War II:
Most occurrences of "bloody but unbowed" in recent years omit any reference to a head as the thing being so described, but the sense of the expression is not much affected by this omission. Whether a bow is made at the neck or at the waist or at full length, the subservience implied by the gesture is what's important.
There are also a fair number of variants on the expression these days, such "bloodied but unbowed," "broken but unbowed," "battered but unbowed," and "beaten but unbowed." Nevertheless, all of them seem to have originated with Henley's formulation, which, I think, fully qualifies as a proverbial phrase in English, if not as a standard idiom.