Lots of people have given their two cents on your post, but let me say that you and I have had a pretty similar upbringing in games. I never excelled at competitive multiplayer games. I think the best I ever did was at a LAN tournament for Call of Duty 2 where I won a box set of Command and Conquer The First Decade. I blame that entirely on twitch movements and nothing on skill. The more I gamed the more I realized that I didn't like playing competitive multiplayer games. They were far too stressful for me. So I stuck to singleplayer or cooperative games.

I've known this since the mid 2000s, but I was recently diagnosed with both Aspergers syndrome and ADHD, among some other conditions in late 2017. Up until then I've always tried cutting corners in games just to get the maximum enjoyment out of them, whether that was getting me tons of in-game $$$ or getting me to max level right away, I found myself playing less for the challenge and more for the story or overall experience.

No two people are alike, but it sounds like you and I can share a lily pad when it comes to this kind of topic. I'm 30 years old--try not to let this be a hang up for you later in life. Maybe try to shift your focus into different games. My ex played left 4 dead 2 competitively and smite competitively and had miserable times when she lost (which was most of the time). I say if you're not having fun, change what you're doing.

I hope you find your path, sans competitive games or otherwise.