Not to get into HP discourse in Anno Domini 2021, but Snape's story isn't "Oh he's a pathetic Nice Guy who won't stop stalking a girl even in death"
His story is that of a man who self-sabotaged his only healthy friendship bc of the toxic patterns he learned from a lifetime of +

neglect & abuse. He never gets to make amends, & learns that the hard way when death closes & locks that door forever. Then he spends the rest of his short life in guilt & self-hatred over it, both wanting to make amends & believing it's a lost cause. This makes him miserable +

& ruins any chances for most other friendships & other relationships to develop. And yet the seed of that one happy memory lives on & inspires him to make the ugly sacrifices nobody else will.
It is, in fact, a tragedy. I understood the point & meaning of it by age 17. +

& honestly if all you ever saw was the story of a Nice Guy who was bitter about losing a girl, then maybe count yourself lucky that you've never been in a position to understand his character arc.