My partner is ruining our relationship with his game addiction.

Hi all, I’m really at a loss here and this is my last resort.

My partner and his younger brother have a seriously bad gaming addiction, specifically a rocket league addiction. I live with both of them and have essentially watched both their mental health decline and attitude changes in the last 6 months. They play together almost everyday. Unfortunately every night is an argument about how the game is bad for my partner and usually it ends in him ignoring me and being super loud playing with his friends and brother and me in tears being kept awake by him. Yesterday was my breaking point, for context I live away from my home country and found out that someone very close to me passed away. It was obviously very difficult news to hear and my partner spent the day comforting me then went out for dinner with his brother and their friends for someone’s birthday. They both came home and decided to play rocket league together. I was exhausted from crying all day from grief and was very keen to go to bed. About an hour into them playing rocket league I asked him if he could get off the game soon because I want to go to bed. He explained he was in a tournament and couldn’t just “get off”. I could hear his brother yelling and smashing his controller on the desk from frustration about the game and asked my boyfriend to tell him to be more quiet. We then spent the next hour (it’s probably 11:45pm at this stage) arguing with me crying and begging him to turn it off and him ignoring me or saying he can’t. They got to the final of the tournament (which I didn’t realise was a big deal) and at my wits end I unplugged his playstation from the wall switching it off completely. He was absolutely furious and smashed his controller on the desk shouting “what is wrong with you!! why would you do that” and then his brother came out of his room and flew into an extremely scary rage. He started screaming saying he spent 2 years working towards this moment and it’s all fucked up now and how rocket league is the only thing that makes him happy and how he wants to kill himself etc. I was physically shaking and all my boyfriend could say is “you caused this”. He genuinely doesn’t see an issue with the fact his brother blew up like that over a GAME. They enable each other severely and it’s getting to a point where my boyfriend is actually horrible to be around the second he switches his playstation on. I keep telling him it’s ruining our relationship but he genuinely doesn’t seem to give a fuck. Does anyone have a similar experience or advice on how to go about this? I really love my boyfriend but I can’t continue on like this anymore.