I don't know, If it was me I would find it hard to restore relations after this whole situation. The guy behaved like a total moron and there is no guaranty he would not do something similar in the future "out of consideration". Author should have not done this in the first place - it ruined the whole story IMHO
At least author himself is aware of how shitty and stupid this situation is...
the whole "spineless mc thinks he's not good enough and tries to distance himself" thing feels so common that it was satisfying seeing him get bluntly told off like that
The little sister is right but she s being a bitch about it, "u made something nice for me and it made me feel guilty so it s your fault" like what was he supposed to do, fuck off to the concert or tell his sister "hey this is your fault", hell nah he made the right decision for his sister just not the right one for the girl