Consider that your little brother is going to love you whether you play minecraft with him or not. Also consider, that by playing for long periods of time with him, you're also acting as an enabler for him, also putting him into the cycle of deriving contentment not through personal challenge but through the cycle of gaming achievement. The key, is in recognizing moderation. You don't have to uninstall and not do this thing you enjoy anymore. You just have to set aside reasonable blocks of time, and hold yourself to them. Your brother will understand if you say, "hey buddy, I can play this with you from 5-8 tonight, but then I'll be busy for the next couple days, etc.) You set what works for you, what allows you to draw the balance between "I'm spending time with my brother" and "I'm leaving myself enough time to do the things that are important to improving myself as a person."

Yep, I think that I'm going to do that, currently I'm playing with him almost every day, but I think I'll limit myself to once/twice a week and only for 1 or 2 hours.

Blocking it all, going the nuclear option, will just cause you to relapse. So, assign yourself periods of time when it's okay, and then hold yourself to them.

Wouldn't it be the opposite that would cause me to relapse? For example, the nofap guys don't fap once a week instead of 5 times a week, they just never fap, and eventually they overcome that addiction.

However, I want to impress upon you, that at the end of the day, an internal support mechanism is required to hold your nose to the grindstone. You have to want it. You have to want the "life you see when you close your eyes" more than you want the source of instant gratification in front of you.

I don't quite understand that bit :/

Good luck!

Thanks :)