Overwolf is a good example of software that lets you watch a recap of your death every time you die. You still did not play perfectly as perfect play is impossible, so always seek ways to continue improving. It was a personal victory you as an individual experienced. If you play a game relatively well, congratulations! No matter the outcome of the game, you just won. (I understand venting about such things help relieve the frustration of losing - but if you are playing to improve rather than to win, you will be much less frustrated and over time climb faster and further than you would have been able to otherwise.) Letting them get to you only hurts your chances of climbing over time, because by focusing on these things that you cannot control, you lose focus on the one thing you CAN control. If you are trying to learn more about LP or MMR to blame the system, you are not focusing enough on yourself. If you are blaming luck or teammates regularly for your lack of climbing, you are not focusing enough on yourself. If you are hatching Riot conspiracy theories about them trying to keep you down, you are not focusing enough on yourself. If you are participating in a flame war in team chat, all chatting about how bad your jungler is, looking up a teammate to see how bad they are so you have an excuse as to why you lost the game, you are not focusing enough on yourself. Simply playing the game and truly analyzing your plays/mistakes does not leave a lot of room to focus on much else. There is literally no game you’ll go through where you don’t make mistakes (bad choice, bad trade, died to ganks that could have been avoided, etc.) So every game there is plenty opportunity for you to learn from your mistakes. Do not focus on LP, or MMR, or your teammates, or even what tier or division you are in! Go into every game doing your best to focus on yourself. Reframing the situation to focus on yourself and accepting the other factors in the game as things you cannot control. My favorite option though is trying to reframe the situation, which is often a solution to overcoming loss aversion. How do you overcome this? There is more than one option and different players might find different solutions. This can tilt you, lead to toxicity, make you play worse, worsen your mood, etc. So while your win/loss ratio might sit relatively close to 50%, the losses stick with you harder than the wins.
Loss aversion refers to people's tendency to prefer avoiding losses to acquiring equivalent gains. Hating losing is not the part that causes problems for many players though, the biggest problem is that people hate losing more than they like winning. Even players much better than their elo suggests still end up with about 60-70% winrates as they climb, falling slowly towards 50% as they come to climb and play against players with similar solo queue ability.
A truth many players fail to realize is that you are going to lose almost half your games. Especially losing the games where it feels like the result of the match is entirely out of your control. A huge part of the frustration that comes with playing League of Legends, is losing.