->''When they are alone they want to be with others, and when they are with others they want to be alone. After all, human beings are like that.''
-->--'''Gertrude Stein'''

Physical solitude, or mental (which can be worse in a crowd) -- and its causes, and its consequences.

A total lack of human contact can leave the character isolated even if surrounded by non-humans; and sometimes they have to be specific kinds of humans, and sometimes, no one can keep them from feeling isolated.

Compare IntroversionTropes. Contrast {{Ensembles}}, PowerTrio and DuoTropes. See TheSinglesIndex, which deals with romantic solitude.
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!!Tropes
[[index]]
* AloneAmongTheCouples: A character with no loved one is surrounded by those with loved ones.
* AloneInACrowd
* TheAloner
* AloneWithPrisonerPloy
* AloneWithThePsycho
* AttractivenessIsolation: An attractive character is alone because no one dares to ask them out.
* CantLiveWithThemCantLiveWithoutThem: A character is stuck with someone against your will, but realizes they miss them when they're alone.
* CityInABottle
* DarkMagicalGirl
* TheDrifter: A character that is WalkingTheEarth.
* DyingAlone
* EatingLunchAlone: A character is found eating by himself only.
* FigureItOutYourself
* FriendlessBackground
* GoMadFromTheIsolation: When being alone causes a character lose their sanity.
* HatesBeingAlone
* HeadphonesEqualIsolation: A character with headphones on pays the world no mind.
* TheHermit: A character lives in solitary and likes it like that.
* HermitGuru
* HeroicNeutral: A character wants to be alone and have nothing to do with anyone else.
* HiddenElfVillage
* {{Hikikomori}}
* IJustWantToHaveFriends: A solitary character longs for friends.
* ImNotHereToMakeFriends: A contestant is focused on winning the game as opposed to making friends with other contestants.
* InTheEndYouAreOnYourOwn
* IneffectualLoner: A character's solitary nature is not enough.
* InformedLoner: The narrative implies he's a loner, but he's shown to be with friends.
* IntelligenceEqualsIsolation: Intelligent people are loners.
* ItsUpToYou
* IWorkAlone: One character can do the work of five. Usually a OneManArmy.
* JunglePrincess
* AKindOfOne
* KnightErrant
* TheLastManHeardAKnock
* LastOfHisKind
* LeaveHimToMe
* LeaveMeAlone: A character rejects others' help because he thinks he can do it on his own.
* LeaveTheTwoLovebirdsAlone
* LonelyAtTheTop
* LonelyDollGirl
* LonelyRichKid
* LonelyTogether
* LonersAreFreaks: When being a loner is labeled as being weird or evil.
* LonerTurnedFriend: A solitary character becomes a friend to someone.
* LonersWillStayAlone
* MaddenIntoMisanthropy
* MinorLivingAlone
* MisunderstoodLonerWithAHeartOfGold: The loner isn't bad as people make him out to be.
* NatureHero
* NoSocialSkills
** NotGoodWithPeople
* OnePersonBirthdayParty
* OneRiotOneRanger
* TheOnlyOne
* OrphansOrdeal
* ParentalAbandonment
* RememberThatYouTrustMe: A character is reminded they have friends.
* {{Robinsonade}}
* TheShutIn
* SingleLineOfDescent
* SingleSpecimenSpecies
* SmallSecludedWorld
* SoleSurvivor
* SolitarySorceress
* SoloSequence
* SurvivorGuilt
* ThereIsAnother
* TheyreCalledPersonalIssuesForAReason
* ThisIsSomethingHesGotToDoHimself
* TraumaSwing
* UniquenessValue
* UsedToBeMoreSocial: A character used to be close with others, but is now withdrawn.
* WildChild: A character that was born and raised in the wilderness.
* TheWorldMocksYourLoss
* ZenSurvivor
[[/index]]
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''Quite a crowd of them, isn't there?''
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