Being in top form for tournaments, you have to shoot in a lot of them. Right now I'd get slaughtered in a tournament, even if I don't miss any balls on the practice table or do good matching up.
My weakness in tournaments is the sitting and waiting game. I do my best just walking in a place, play and leave. If I have to sit for an hour or more, I lose interest so quick no matter how hard I try to keep the interest alive. As long as I'm shooting, I can shoot for hours.
If I could shoot in a couple tournaments a month on 9ft tables near my location with matching up, I might be able to do well. But chasing just the few tournaments a year and the cost, just isn't practical to me. I gave up trying to figure that strategy out. Every man has his limitations and I found mine. lol
Giving up is an option and this is your decision to make. Reading between the lines there is a player with a passion who wrote this. Years ago I ran across a game called "equal offense". It was based around straight pool. The thing is it starts from a break, then basically ball in hand. An inning is limited to 20 balls, straight pool style. The neat thing about the game was an opponent on site wasn’t needed. The game was made to address your competition issue. You could play against another player anywhere using any game. You each start from the same scenario. A scoring system is needed giving each ball weight. In order to give some value to safety, a point could be awarded if it is called and successful. The inning is then over either way but keeps safety play in the game. You would specify a number of innings for a match and compare scores. The players don’t need to even play at the same time.
A forum like this could be used to actually set up matches. Like minded players could set up tournaments. This format was used prior to all the mobile devices with video. When I played trust was a major issue. Another issue is comparable equipment since each player is using a different table. Pool hall owners and billiard instructors could tap into this format. They could arrange for matches between students they are training. Instructors often link up with players from different regions. Letting players play and develop without the expense of travel and entry fees in a competitive scenario addresses a problem for players such as Ken.
Other players use the ghost as a format simulating an opponent. The point is that the issues listed by Ken are just that; problems. Creating constraints on how things need to be to solve a problem creates a McGyver test. Chasing a dream sometimes means people have to be creative.
The competition mindset is another issue. Creativity in excuse making is not a tactic. Not meant to be harsh. Meant to emulate what you likely would say to someone who was frustrated, saying they want to quit, but really don’t. Try something different when what you are doing doesn’t work.
Distractions can be a botch. I simplify. Getting out of the venue is a good idea. Find something like staying down, finishing the stroke, or quiet eyes, a behavior you need on every shot. Dedicate your time away from the table to different kinds of imagined shots, with that behavior there in every imagined case. You say you can shoot for hours, shoot in your head. Ingrain a good behavior while you do.
In venue behavior needs to have its own pre-game/in-game routine to handle issues not pool related. I don’t initiate conversation. I’m not rude, I answer if talked to but don’t sustain conversation threads.
Keep your eye on the tournament ball. Make sure you know what to do, where to go, how to tick all the not at the table boxes. Check and organize your equipment, your away from the table space, and needed resources, like water, bathroom locations. Get your ducks in a row.
Distractions in the room, while playing. Bookmark your on table activity. Give your full attention to whatever has drawn your attention away. It usually is over quickly or gets boring real fast. Then "ok where was I". I sometimes even restart by vocalizing the on-table situation. "Oh yeah, that 3 ball can go there and the cue ball needs to come in this area for the 4 so I have angle to get to...". Stopping then talking to yourself may seem strange, but getting distracted, missing the shot or position can sit you in a chair. I prefer to be at the table. When you vocalize, hearing your voice and its directions focused on the table, keeps you out of your head. An outward focus on what needs doing.
Each thing here was a solution to a problem. Have a plan, not an excuse. If the plan fails, so be it, at least you tried. Meant to be helpful, not judgmental. Other players reading this thread may relate to your problem and not want to quit, just want ideas.