At different points in his life, Snape is each of the brothers in the tale. In youth, he was combative. After Lily died, he wanted to join her in death. But for his second chance in life, he has been keeping his true self hidden, not for personal gain but in order to protect others. According to Dumbledore, that is the essence of the Cloak of Invisibility, “the true magic of which, of course, is that it can be used to protect and shield others as well as its owner.” (HP/DH, 716)
snape as master of death, by the very fact that he didn't want or need ANY of the hallows at any time
he didn't need the resurrection stone, the only person hed call back is with him every time he casts his Patronus
he doesn't need the invisibility cloak, hes the spy, he knows how to hide himself until the perfect moment
he doesn't need the wand, he never wanted power for himself but always acted defensively
maybe Snape was so sensitive about being called coward was part of that, he acted defensively, he didn't attack like James when it was 4 on 1, or like his father who would be violent and that's what he called cowardly so to be judged that way burned him....??
