I'm looking for an Anime/manga/novel/book that the protagonist was brought into despair the moment it started, and because of that his outcome in life depends only for himself but as time goes by, people starts gathering at his/her pace. something with that kind of idea. thanks!

Tate no Yuusha no Nariagari MC gets betrayed and branded as a villain and can't trust anyone, but gains both friends and revenge as the story progresses.
Übel Blatt MC gets betrayed and killed. Resurrected years later, he hunts down those that betrayed him all the while being known as a villain. Gains friends and support.
Skip Beat! MC works hard to provide for her boyfriend's dream of being a rockstar. Only to find out that he doesn't love her. Heartbroken, she can't feel love anymore and joins the entertainment industry to beat her ex at his own game.
Arifureta Shokugyou de Sekai Saikyou (Novel) The entire class is transported into another world and given fantastic powers... except for the MC. He gets shitty ones. To make matters worse he is constantly bullied and eventually left for dead. Only to rise from the ashes of his former self as an invincible MC who has killed his feelings.
Accel World MC is bullied and weak. Is found by his love interest who develops and interest in him and helps him grow to become a better person.

You can check out the betrayal tag here as well. https://www.mangaupdates.com/series.html?page=1&orderby=rating&category=Betrayal

thanks!

Kumo Desu ga, Nani ka? (Novel) well almost fitting except for the fact that she doesn't get it back becouse .... of avesome reason you should find yourself 🙂

Cradle of Monsters
Destroy and Revolution
The Meteor

Koe no Katachi MC used to bully a deaf girl, but it eventually backfired on him. He's put on the verge of suicide before an encounter with that same girl makes him want to set his life straight. People slowly start to gather around him over the course of the story, but it's not always for the best. This manga is completed.

Iris Zero MC is one of the few kids whose eyes don't have a special power. He made up his own power, backing his lie up thanks to his spirit of observation. But when the lie is exposed, he's left alone. However, it's not the end for him, as he'll slowly be able to make friends. This manga is on hiatus.

Angel Densetsu It's kind of a parody of the type of story you're searching for. MC is believed to be a delinquent because of his scary face and unfortunate coincidences. The fact is he doesn't realize that he's being feared, nor that the friends he's making are actual delinquents. Hilarity ensues. This manga is completed.

My current top 3:
Fullmetal Alchemist
Pandora Hearts
3-gatsu no Lion