I'm worried about my boyfriend's behavior with video games

I'm worried about my boyfriend and I'm not entirely sure how to approach talking to him about it.

I'd like to preface by saying we both play video games. They're fun, I think they're a good way to relax or have a new world to explore or just have a feeling of accomplishment, depending on what you're doing. My boyfriend has played video games his entire life. He and all of his siblings were raised on them. He's really passionate about a specific game you can play online that he's liked since childhood.

But lately when he's played, he's gotten extremely volatile. Like, screaming and pouting and swearing like a child ("F*** you, you c***", like really aggressive things), and he's an adult man. I get mad at games too, but when I do, I put them down and come back later. I used to have a problem with getting upset, but I pulled myself out of it and distanced myself from games that made me feel like that because it made me worried. But he just keeps going into the night because he "just wants to win one goddamn match" to feel like he's "accomplished" something. That really really worries me, because that can lead to addictive behavior. It's also getting pretty frustrating for me emotionally. For one thing, I wake up early. I have classes and work. I can't handle someone yelling and swearing late at night. It also puts me on edge emotionally because I know even though it isn't directed at me, he has the potential to be that angry and scary. He also seems convinced that video games "calm him down" and are helping his mental health somehow, that's what he's said when I've talked with him about this before, like it's a "release" for him. I've only ever seen them make him more on edge, especially more competitive ones. It also doesn't help that his siblings who we are close with are just as entrenched as him, if not more. Their girlfriends have spoken on more than one occasion about feeling neglected by their gaming habits. I don't want us to get like that.

I want him to be able to keep playing games, and I want to play games with him together. But I'm really worried they're being used as a crutch or coping mechanism for something deeper, or that they're warping his personality, or making him more angry and on edge. He wasn't like this when we started dating at all. I know many people who have mental health struggles can overrely on gaming, and it tends to do more harm than good in those situations. I want to be able to be around him playing games when he isn't so angry about something he shuts down or blows up. I don't know how to bring this up to him without hurting his feelings or making him feel bad somehow, because I just KNOW there's something going on inside that isn't good right now and I want him to get help. I don't want him to get addicted and play into the night, yelling and screaming. I just want my happy boyfriend back.