Yumemiru Danshi wa Genjitsushugisha Episode 3 Discussion

well... this finally materialized into the usual trope of "Toxic relationship the anime" with flavour of:"How to gaslight your partner into being complacent in abusive relationship". 

I resent the japanese way of making fun and comedy out of mental illness/abuse/psychological stuff, yet they do it all the time and so casualy that I question what their cultural take on it actually is.

Tsunderidnes to the point of *violence* for the character that we are supposed to root for just.... doesn't work for me

I wouldn't call it "being abused". The section was a bit nuanced so maybe some details were overlooked when you watched but basically she was just being the tsundere sister who talked cold but actually cared which is how he saw it. He knew she cared and this is why he told her to keep acting the way she has because he essentially understood his sister actually genuinely cared despite her cold exterior. However, she came to be aware of a situation where something similar happened to another party in the past, but more extreme, which resulted in severe consequences... and she thus over analyzed and took her behavior to be more severe than it was when, in reality, she wasn't really insulting him harshly but treating him like he was kind of average in contrast to many other examples of other characters actually treating him more harshly such as the face comments. She grew critical of her behavior and worried his sudden change with Aika after all this time was something more serious but the understanding brother reassured her that he understood how she really felt but also somewhat played into the fact that the MC does, indeed, not have proper confidence in himself though the issue isn't really due to his sister as he said. Its a complicated and nuanced scene that branches into his underlying issues elsewhere in the story and has quite a few layers for both him and herself. He also recognized that she wanted to change because she was seriously concerned and acknowledges her concern, regardless of how he says for her to just keep being his cold aloof sister.

It does help setup his own issues with confidence though after his friends and the past story of him being trashed by the girl he liked being seen in the first three episodes. He truly doesn't have proper confidence despite many people around him thinking rather well of him. It kind of reminds me of The Angel Next Door Spoils Me Rotten's MC issues and some others with the trope of a actually good person just excessively undervaluing themselves unnecessarily.

I think you might be on the wrong anime forum. If you think you aren't could you possibly elaborate on like... all three points? I can't see this referring to the anime in question tbh.