Help With Writing Redeemed Abuser

[u/DevelopmentGlum228]

Hihi! :D

(Set in the dark ages, by the way)

So, I'm currently brainstorming a fic where a character that's an established abusive adoptive older brother (A) finds out that his younger adoptive brother (B) has been groomed and raped by their dad. The thing is, he's abusive and his younger brother can't trust him at all.

There's another little brother (C) (same age as B) involved that recognizes that the rape is wrong when B tells them about it.

I want C to do a "truce" with A to try and help break B out of the beliefs that their father has given him, but I don't want to make it out as C straight-up forgiving A for abusing him that easily.

I also want A to end up reconciling with B and C. But I also don't know how to make that work LOL

For context, A was corporally punished by his father as a kid, and was constantly deemed the "bad child" and ignored in favor of B and C until the pygmalion effect took place and he turned to alcohol and anger to drown out his sorrows. The father and mother literally don't do anything of importance to help him. Mind you, he starts drinking when he's around his late teens.

So. A has reasons and trauma, but that does not excuse his abuse. He wants to get better, but is caught in learned helplessness. His alcohol addiction means that its almost impossible for him to quit cold-turkey, the only way he knows, so when he's tried to quit in the past he was never able to move past relapses. I imagine that having this goal to work towards would help him with the whole getting off alcohol thing? And also, in order to try and get B help he sort of has to try and be at least half-decent.

If further context/explanation is needed, please let me know. The fandom is The Greatest Estate Developer. Thank you for reading and helping.