I get why people recommend the obvious power fantasy isekai stuff for this, but those usually miss the emotional weight entirely. The real books that capture rebirth as an emotional process are quieter. 'The Blue Salt Road' by Joanne M. Harris isn't strictly reincarnation, but that selkie's cyclical return to the sea and the painful shedding of a human life? That's rebirth. The emotion isn't in getting a second chance to be strong; it's in the grief of what you leave behind each time you're remade, the saltwater memory that never fades.
For something more direct, 'The Invisible Life of Addie LaRue' handles a weird, cursed form of rebirth—being forgotten by everyone she meets. Every single day is a rebirth into anonymity, and the emotional core is her desperate, centuries-long fight to leave a mark, any mark, on a world designed to erase her. It's less about reincarnation into a new body and more about the soul's need to be witnessed, which is, frankly, a sharper angle on the theme.
Most lists will point you to cultivation novels or villainess manhwa, and sure, those have the premise. But the emotion often gets buried under system screens and revenge plots. The best ones for the 'emotional rebirth' brief make you feel the disorientation, the haunting echo of a past self in a new reality, not just the tactical advantages.