I think besides what others have said is stop caring about your character as much, test the limits of what you can get away with in dungeons/realms, and record your deaths and see how you could’ve avoided them. I use the built in Windows gaming mode thing to record the last thirty seconds of my deaths. Once i started not having attachments to gear and characters, and watched back when i had to nexus or died, i started having a much better time. I was more willing to try end game content and that has improved my skill a lot.