Wikipedia:You are not irreplaceable
You are not irreplaceable is an important concept to remember in a worldwide collaborative project like Wikipedia. There is no editor who is indispensable to the Wikipedia project, or even to a given article, topic, or situation within the project.
No editor is so important that the Wikipedia project would collapse without them. An editor may have hundreds of thousands of edits, hundreds of GAs, FAs, dozens of barnstars and a legion of friends-and-relations; nevertheless, disruption is disruption, tendentious editing is tendentious editing, and harassment or Wikihounding is harassment.
Such an editor deserves kudos for their achievements and sanctions for their disruptions; the one does not cancel out the other. Other editors should address disruption when appropriate and not skirt the issue for fear of driving off an important or esteemed editor.
If you're that editor, your contributions, while very much valued, don't absolve you of behaving like a reasonable, civilized person. You're not indispensable to the project: to create a collection of the sum of all of the knowledge of the world. Together. While being civil to each other.
You are important
Every good-faith editor is important to the overall success of Wikipedia. Many positive changes are made by IP-address editors, or editors who have no desire to make an ongoing hobby out of Wikipedia. A mass of people making one or two positive contributions to Wikipedia keeps our encyclopedia updated, fixes errors, and actually does the bulk of the work.
At the same time, there is a pyramid of editors who make more edits than most – these highly active editors form the backbone of the project, working to keep everything flowing smoothly. Some of these editors become administrators or assume other roles tasked with more authority and responsibility. Others perform equally important tasks such as informal dispute resolution, programming bots, rescuing articles up for deletion, or chairing collaborative efforts. Of course, all of those processes exist to support the gifted editors who produce our articles and function in our audited content areas such as DYK, good articles, and featured content.
You can take a break
Wikipedia is a hobby. If you ever begin to think Wikipedia will fall apart without you, you're almost certainly wrong. While there are many people who are important, anyone can be replaced. If you are involved in a community process and you're the only one doing it, consider enlisting someone else to help. It's been said that in a volunteer organization, one's first task upon taking a new job is always to train one's replacement, and Wikipedia is no exception.
Wikibreaks are often required by real life events, and no editor should ever feel guilty by taking the time they need to deal with family, work, school, or other situations that demand their attention. If Wikipedia editing is making you stressed, you may need to take a Wikibreak to cool off.
Editors who are unable to appropriately depart from Wikipedia in order to deal with real-life issues often suffer consequences in the neglected areas, become burnt-out on Wikipedia, or both. In no case is any of these outcomes helpful to the editor or the project.
You can be replaced
If you need to leave, you can be replaced. If you were doing an essential function without anyone else helping you, either the community will do without or someone else will take over and pick up where you left off. Either way, you don't need to lose sleep over the fate of your Wiki-work.
On a more sober note, no individual contributor is so essential that consistent poor behavior will be tolerated. While it is true that idiosyncrasies are more tolerated in established editors with a track record of good contributions, the community has sanctioned any number of editors who made positive contributions to the encyclopedia because their behavior failed to uphold the civility pillar.
Sometimes, it seems like you're the only one holding back the barbarian hordes, which, to different editors may include new users, IP editors, people without a track record of contributing on a given article. If you were to step away from the article, all hell would break loose, the encyclopedia would be irrevocably damaged, the fabric of civilization would be rent asunder. You may feel that no one else cares about the article, no one else can defend this bit of the encyclopedia.
If you feel like this, you need to step back. Take a Wikibreak. You can reach out to others in the Wikipedia community for help. You are not indispensable. There are always other editors who can help out. New editors. IP editors. There are always editors patrolling for vandalism. There are always editors watching out for WP:BLP violations.
But, more importantly, when you feel like this, you are right on the edge of the WP:BATTLEGROUND (feeling like Wikipedia is a "battleground", rather than a collective encyclopedia project) and it's likely that your continued participation will, in fact, make the situation worse, not better.
It's better to call for help, step back, and let other, more impartial editors take over.
Watch out for the feeling that you are indispensable to the project, to a certain article, or to a certain topic; it probably means you may be getting close to engaging in inappropriate Wikipedia behaviour (e.g., edit warring, Wikihounding other editors) that could lead to you being dispensed with from the project, via a block or ban.