Frankly this is a struggle that many of us chess players can sympathize with. We do everything, try to improve our middlegame hope to find that opening book which will always give us a superior middlegame, we do everything, hire coaches etc. And then one harsh loss sends us hurtling back to right where we started and so we begin once more with the same exercise.
Good bye and good riddance

Take a break, take a walk, get some air...
Good food, a hot shower, a stiff drink and get some rest...
Its not how many times you fall my friend. Its how many times you get back up that count. 🙏

I'm not as good as you judging from your rating. But I'll say this about Time. Like another guy said that's part of the game. The winner is who can make the best moves within the time given. In years past there were world championships with no time control that lasted for many many hours. IMO that's too extreme. There are many different time controls in OTB tournaments. I wonder what time control you lost in? I recently played in a G120 d/10 tournament. That is 2 hours per side and the game can be up to 4 hours long. (A note here is that young players never resign and never draw. So if you are 3 pawns up, then you are going to spend 3.5 hours checkmating them). Frankly asking for a game longer than that is ridiculous. If you like rapid then play G/45. If you don't, then play G/60, G/90 or G/120. But if you are losing on time in all of those, then you will just have to admit to yourself that you are not as good as your opponent who can make good strong moves within the time given. They aren't going to create a G/240 tournament because some guy wants to spend 8 hours playing one game.
Having said all of that I think I might never play Blitz. Because my only chance at playing a good game is in a slow time control. I'm terrible at blitz. But when I play a clown who makes stupid moves fast and beats me on time, then I realize they are the better blitz player. But since I don't care to play like that I don't play blitz. I know blitz is fun, but (right now) I'm not interested in learning a bunch of tricky unsound openings that win because the opponent doesn't have time.

Context: this is a copypasta originating from the smogon classic, one of the largest competitive pokemon tournaments there is. In the semifinals, Lavos, who is one of the biggest names in the community, was up 2-0 in a bo5 set. His opponent Soulwind then reverse 3-0ed him largely in part to extreme luck in multiple games. He then posted in all seriousness, the original version of the copypasta, and was banned off smogon. Op is some high and mighty prick. Just another dude on the internet trying to meme.

I'm not as good as you judging from your rating. But I'll say this about Time. Like another guy said that's part of the game. The winner is who can make the best moves within the time given. In years past there were world championships with no time control that lasted for many many hours. IMO that's too extreme. There are many different time controls in OTB tournaments. I wonder what time control you lost in? I recently played in a G120 d/10 tournament. That is 2 hours per side and the game can be up to 4 hours long. (A note here is that young players never resign and never draw. So if you are 3 pawns up, then you are going to spend 3.5 hours checkmating them). Frankly asking for a game longer than that is ridiculous. If you like rapid then play G/45. If you don't, then play G/60, G/90 or G/120. But if you are losing on time in all of those, then you will just have to admit to yourself that you are not as good as your opponent who can make good strong moves within the time given. They aren't going to create a G/240 tournament because some guy wants to spend 8 hours playing one game.
Having said all of that I think I might never play Blitz. Because my only chance at playing a good game is in a slow time control. I'm terrible at blitz. But when I play a clown who makes stupid moves fast and beats me on time, then I realize they are the better blitz player. But since I don't care to play like that I don't play blitz. I know blitz is fun, but (right now) I'm not interested in learning a bunch of tricky unsound openings that win because the opponent doesn't have time.
Time is something we cannot control. To play chess right we must take our time to find the best move, however time restricts that. It's an unfortunate paradox.
For those who are saying time is a party of chess, think about this. You are discriminating against those who think slower. This is something we cannot control. We also cannot control the color of our skin. Saying time is a part of chess means that you are a racist.
I too have, and still do, lose many games where I have been on top through time pressure. Nervous tension gets the better of me too. Of course, it's hugely frustrating and demoralising. But in this life aren't we meant to get back on the horse? Here is a piece that I refer to when the need arises. It is from IM Andrew Martin: "And when you are defeated - KEEP CALM. (His capitals.) I have known even very strong players completely lose their objectivity and self-belief during a bad patch. Some even give up the game. That cannot be the way! So resolve to learn the maximum possible from ALL your games, work as hard as you can within your own limitations and chess will open its secrets to you, providing a lifetime's entertainment."
"Unfortunate" doesn't begin to describe my time playing chess. This game rewards blind luck and nothing else, I am beyond convinced at this point. I recently lost an OTB game on TIME, losing this way somehow felt even worse than I thought possible. My preparation was superior, my play was superior, and I lost, so I don't see a reason to continue engaging in an activity where what is within my control is overwhelmingly outweighed by what is not.
I am done with chess, and you won't get a fond farewell. This community is infected to its roots with a degenerative disease that grows stronger over time but stops short of killing its host. Tournaments used to have a competitive spirit at their heart, this has been transplanted and replaced with an artificial organ that feeds on vitriol and mockery from insecure little boys that heckle by the sidelines and tear each other to shreds over scraps of attention. The environment we fostered has trapped us all like this in a vicious cycle and escaping it requires acceptance of the harshest reality we all scramble to explain away, that none of the countless straining efforts we put ourselves through here will ever amount to one single shining glimmer of significance. I would make this the end but I'm in the middle of a tournament, I wouldn't want to waste my money so I'll suffer through a few more games.
One last thing before I leave you all to react with disdain, ridicule, and self-righteousness fervor, before you do everything in your power to minimize my words and thoughts, box them up and shove them to some cobwebbed corner of your memory, and hope they disappear forever as a stain on your finite time ground to dust. From this moment on, nothing you say matters to me. The foulest insults you hurl with intent to wound will calmly settle at the earth before my feet, and the venom you spit will bring all the pain of a warm summer breeze. You are less than anything you can conceive, while I carry on, brimming with joy distilled from detachment.