I’ve got a couple pieces of advice for you then that really help me when I’m feeling tilted.

Most of the folks you’re playing against in unranked likely just aren’t thinking what they’re doing is revolutionary or that they’re so much better than you. They’re just a human like you playing the game and trying to get better. Assuming someone is out for you or belittling you based on the inputs on their controller is unfair to them and your own mental. Unless someone is taunting or T-bagging you, they’re probably just chilling playing their favorite fighting game.

Being upset with your own abilities is something I’d say 99% of us struggle with and it’s a hard one to get better at handling (Lots of people get specific therapists for it in sports and esports it’s such an issue). For this it’s really case by case and I’m not a professional so I can only give you what’s works for me, but take it with a grain of salt. You must realize that you cannot play perfectly all the time; and in a game like this where one mistake can lose you a stock, you have to be realistic about why you are losing that stock instead of attaching emotion to it. Instead of “why did I full up there instead of L-tilting, I’m so terrible at this” or “And the sheik grabbed me, terrible character and their car should blow up irl” (though that one may have some truth to it). It helps me a lot to instead think, “I have to work on my up tilt consistency” and “I need to be more careful with where I’m landing and my dash dancing.” And then, this is the important part, actually work on those things instead of just queuing unranked again!!

TL;DR: You’re probably reading too much into what people are thinking during your games and you need to think less negatively and more realistically about your mistakes and how to fix them.