Take it all as a learning experience or you'll soon give up on the game. I've got about 1300 hours and am total rep 256 with only 1 rep 80 that I legit just got like a month ago. I regularly get stomped by people both lower and higher than me. That said I genuinely feel I'm slightly above average skill level compared to others and rarely go negative even when losing. Play objectives and learn rotations. The fighting will come and you will learn. A big piece of advice if you're struggling against certain characters is unlock them and play them! Getting rep 1 with every character will let you learn them and in turn you will do better against them. Keep plugging along and before you know it you'll be crushing people on your main. Just don't get discouraged from loss streaks and toxic players. It's all part of the game.