I really need an advice (TO MUITO PUTO)

venture was the very first DPS that actually fits my playstyle, such unique mechanichs and fun to play, As a casual player I even started playing ranked on them 2 months ago, reached diamond 3 but it became excruciating to play.

I really think that venture is super easy counterable, I always have to carefully manage my cooldowns, then a mf cassidy just press E and kill me, venture has such low range effect that I always have to be in danger zones to get value (no, cover don't save me if I am 10 meters away from the enemy team), its just stressful af. High ground is the only thing that I can rely consistenly, but not all maps enable me to do this.

Not only that, there are matches that it doesn't matter how well u play, u always lose.

I was so mad that I started to lose on purpose, I was hoping to drop to bronze, so I could stomp bronze players (I know this is idiot, sorry). Even if I was playing shit, there are few matches that I won by doing absolutelly nothing, I couldn't even drop to gold. That got me thinking... all matches winners and losers are already decided from the beginning, and theres nothing we can do to change it, I felt so bad, like my impact on the matches was insignificant. If u are masters or above ur probably thinking that I am just a loser making excuses.

Now every match that I play became excruciating, but I don't want to stop playing overwatch.

How can I get back the motivation and joy I used to have on this game?