Hey please don't take this as a commentary on your specific situation, I'm sharing my personal experience and only guessing that it may apply to you as well.
I'm a pretty competitive person in general. I was the guy who will pull out the rule book and call you on a technicality when we're drunk and playing Uno (casual playing card game). When I played Dota I'll tell my teammates what items to build, which rotations to make, when to engage or disengage, etc even if I have the lowest rating on the team. When I played chess I would study openings and variations for hours more than I'd spend playing. I even played obscure open source games with tiny player bases (<100 players) like Bitfighter and Zero-K RTS with the same zeal and obsession as if I were playing for a million dollar prize pool.
When I won, I'd celebrate like I just shot the winning goal at the world cup.
And God help my teammates if they made a mistake.
This intensity was a double-edged sword, with manic highs in victory and white-hot rage in defeat. It's most of why I love playing games so much (sort of like adrenaline junkies enjoy endangering their lives because nothing comes close to the extremity of that process).
As I've gotten older, I've had experiences which exceeded these moments of extreme emotion in their intensity. And as I've gradually had more, I've found my obsessive and unhealthy emotional investment in video games has fallen off almost entirely. After I fell in love, failed at something I worked toward for years, succeeded in spite of that previous defeat, lost people I loved to senseless cosmic misfortune, and in general had a fully fledged human experience it all sort of evened out. The intensity of these real life moments seemed to temper my reaction to events in game.
Team mates fed? Doesn't matter, no one actually died. Got flamed for warping at the wrong distance? Still have the love of the people closest to me. Blundered the counter play to that obscure opening variation? Still professional at something else more meaningful.
Having a well-rounded life experience and investing myself fully IRL has turned me into Buddha in-game. None of it matters, except a moderate thrill of victory from the infectious excitement of my friends.
TL;DR if you find that you've momentarily forgotten you're just playing spaceships with your internet friends, log off and go do something else until you remember that fact.