Currently I read things like arifureta shokugyou de sekai saikyou and suterareta yuusha no eiyuutan, but I would like to read more of that kind. I like strong badass MCs, especially if they were normal at some point and their badass attitude and their strength are the result of horrible and unjust experiences like betrayal (Arifureta) or torture (Tokyo Ghoul) (ahem Did nothing wrong squad ahem).
Thanks for every recommendation!

Tate no Yuusha no Nariagari

Dungeon Seeker

I know Tate no Yuusha (and like it), but Dungeon Seeker is new... it looks interesting!

Lookism may be of some interest to you.

Currently getting my life together~ (unsuccessfully)

You might try search engine with betrayal tag

I strongly second Arifureta. The official English translation of the light novels (digital only now, but physical versions have been announced) just released the second volume. Thankfully, each volume competes with The Rising of the Shield Hero (Tate no Yuusha no Nariagari) for the longest LNs of any LN series I've read so far (official English translations only; I've also only read Shield Hero's physical version).

"Dungeon Seeker" is also the first thing that I get into my mind. Another series that might be interesting is "Moon-led Journey Across Another World" or "Yankee Wa Isekai De Seirei Ni Aisaremasu" (basically everything of LHTranslation is good, this scanlator is doing scanlation of manga's that are adaptions of light novels. They've got a lot of good stuff.)

I also did an advanced search of betrayel and Revenge in the fantasy genre. The series that appear are no surprise, for example: Berserk, Shingeki no Kyojin, Claymore and Tate no Yuusha no Nariagari. But Yaoshenji (Tales of Demons and Gods) and Darren Shan are also in it.
Personally I think you would enjoy the following series:

• Moon-led Journey Across Another World
• Yankee Wa Isekai De Seirei Ni Aisaremasu
• Hiraheishi wa Kako o Yumemiru
• Jaryuu Tensei
• Re:Monster
• Sono Mono. Nochi ni...
• Tondemo Skill de Isekai Hourou Meshi
• Exterminator
• Kouritsu Kuriya Madoushi, Daini no Jinsei de Madou o Kiwameru
• Dungeon Seeker
• Botsuraku Youtei Nanode, Kajishokunin wo Mezasu
• Maken no Daydreamer
• Infectee (webcomic without releases on the moment)
• Yaoshenji (it's a manhua in full color)
• Doupo Cangqiong
• The Legendary Moonlight Sculptor
• Goblin Slayer
• The New Gate

Even after dead, we raise from the ashes for the sake of manga.

I already tried this and found nothing new... But thanks!

Most of the ones mentioned are stories I already knew, but there are some interesting ones, I'm really thankful for your help everyone!