We Were Your Team

"We were YOUR team, Commander. Wasn't much keeping us together after you died."

—Joker, Mass Effect 2

A team falls apart after The Heart or their Magnetic Hero dies, leaves, or ascends to a higher plane of existence. Without his or her unifying influence, there isn't much holding them together anymore, so they drift apart to pursue their own endeavors.

We Cannot Go on Without You is a Video Game-specific subtrope, where the protagonist's death ends the game even if companions are still alive. Presumably they drift apart immediately, without even stopping to use a Phoenix Down.

If the hero comes Back From the Dead, expect Putting the Band Back Together. Compare The Fellowship Has Ended, when the team was held together by a unifying purpose rather than a particular member.

Be warned, this is often a Death Trope, which means unmarked spoilers might lurk ahead!

Examples of We Were Your Team include:

Anime & Manga

When Taichi was dragged back to the real world in Digimon Adventure, the time inconsistency meant that the remaining Chosen slowly split apart over the course of a month or so, partially of their own devices and partially because of the influence of PicoDevimon, to the point that Takeru and Tokomon, formerly very close, even got mad at and left each other. When he makes his way back, much of the next arc is him (and Sora, acting as a Mysterious Protector) trying to regroup the Chosen even as PicoDevimon continues trying to tear them apart.
Pretty much the entire plot of Anohana: The Flower We Saw That Day. A group of childhood friends drifted apart when they were young because one of them died, and now are slowly getting together after the appearance of the ghost of their dead friend.

Comic Books

In Kingdom Come, it was Superman's retirement (after the death of Lois Lane, and the public favoring the Anti-Hero Magog over him) that caused most other heroes to also retire. Similarly his return years later inspired them to come back.

Fan Works

Quite a few One Piece ones had the Straw Hats disbanding once their captain Luffy was gone.

Literature

In the New Testament, after Jesus is arrested and crucified, his disciples are scattered across Jerusalem, not knowing what to do next. Peter even denies ever knowing him (three times). However, then Jesus comes back and rounds them all up again. After his ascension, they once again split up to carry out his will and convert other countries.
In Herman Hesse's The Journey to the East, the tight-knit group H.H. is traveling with completely falls apart after their servant, Leo, disappears in Morbio Inferiore. H.H. later finds out that Leo was actually the League president all along, traveling with them in disguise. His disappearance was a Secret Test of Character which everyone in the group failed miserably.

Video Games

In Mass Effect 2, Commander Shepard's sheer magnetism kept the very mixed Normandy crew together even after the Saren crisis. When s/he was killed, however, they fell apart... See Joker's quote on that above. Shepard's return eventually draws almost all of them back together, aside from those who have other obligations like Wrex reforming the Krogan or Liara being the Shadow Broker. The bulk of Shepard's crew and whichever squadmate you chose to save on Virmire however left on other Alliance business and invoke What the Hell, Hero? for Shepard working for Cerberus.
- This is lampshaded late in the game, when Miranda points out that Shepard must have a magnetic personality and gobs of charisma to get so many people not just working together, but working together well, despite their misgivings about each other. In short, Shepard's superpower is rallying the people.
- Happens again in Mass Effect 3, albeit for different reasons: Shepard decides to turn the new Normandy over to the Alliance and spends six months stuck on Earth. The survivors of the Suicide Mission are scattered across the galaxy, and in a slight subversion, only Garrus and Tali rejoin your squad - everyone else is involved in various side quests.
This happens to the Warden's companions in Dragon Age: Origins if s/he dies in the Final Battle. To be fair, they still leave even if s/he survives.
In Knights of the Old Republic, after the Player Character ventures alone into Unknown Space after the events of the game, the Ebon Hawk crew likewise falls apart, with only a few reappearing in the sequel.
- They didn't just fall apart; they were assigned to different tasks. Canderous was assigned to reform the Mandelorians, Carth is rebuilding the Republic military, and Bastila (and possibly the other Jedi) are rebuilding the shattered Jedi order in secret.
In Persona 3: FES, the SEES members admit they've fallen apart, despite being dorm mates, after the events of the main campaign in which the main character died.
This can happen in Football Manager and whilst it may seem like a weird example all the rules of this trope apply. If you resign or leave your club for whatever reason and you have built a good rapport with your staff then they may leave alongside you.
In The Godfather 2 Michael Corleone discusses this, saying that Aldo Trapani was the only one holding the New York mob together. Sure enough, with his death, breakaway splinter groups have started to form.

Western Animation

This is what happen to the Teen Titans in the episode "How Long Is Forever" after Starfire disappears.
In the one episode of Justice League, when it seems that Superman has been killed, the League briefly considers disbandment. Subverted twice: in the original timeline, they recruit Aquaman and stick around (but don't last long before being wiped out); and when Vandal Savage fixes the timeline, and Superman returns to his time, the League proceeds like they did before.
In the 1990s version of Spider-Man, the Six Forgotten Heroes were implied to have been like this - after Captain America did a Heroic Sacrifice, they each went their separate ways, and most of them gave up superheroism eventually. Although the team is put back together by Spider-man, not Captain America.