The death of Charles Xavier created an alternate timeline, the Age of Apocalypse, in which En Sabah Nur rose to power. The ramifications of Apocalypse’s rule had far-reaching effects and Emma Frost was not immune. Ironically, Emma Frost was not an X-Man or a member of Apocalypse’s elite guard but a leading member of the Human High Council. Little is revealed about how Emma made her way to Europe, from where the Human High Council operated. She alluded to giving up too much to escape Apocalypse. Most telepaths in the Age of Apocalypse were killed and their minds used in the so-called Brain Pool, a defense mechanism of Apocalypse’s citadel. Emma was apparently spared from this fate because she had been partially lobotomized to remove her mental powers. Whether or not Emma was forced into this procedure or she chose it as a means of escaping Apocalypse is unknown. Along with Moira and Bolivar Trask, Mariko Yashida and Brian Braddock, Emma led the Human High Council in their efforts to provide safe haven to those humans who had escaped from Apocalypse’s territories. Knowing that Apocalypse would wipe out the entire human race, the High Human Council mounted a nuclear strike on Apocalypse’s forces in North America with the help of Weapon X and Jean Grey. Naturally, Apocalypse ordered a counterstrike on the human territories, and it’s unclear whether anyone survived that.
In the bleak future reality known as the Days of Future Past, Sentinels controlled North America and most of the nation’s mutant populace had been either killed or interned in concentration camps. Choosing to save herself, the former White Queen of the Hellfire Club retreated to a private, high-tech base on an island off the coast of India. Here, she kept a watchful eye on the world and sold her telepathic services to its remaining leaders. When Wolverine was mind-wiped by the Hellfire Club’s newest queen, Elisabeth Braddock aka Psylocke, a desperate Magneto and Jubilee sought Emma’s aid to repair the damage. Indeed, Emma managed to piece together the shattered fragments of Logan’s psyche. After Logan, Magneto and Jubilee defeated Psylocke and thwarted the Hellfire Club’s plans for world domination, they one again sought refuge with Emma. This ragtag team of X-Men continued to operate from Emma’s island while she made efforts to restore Psylocke to her former heroic self. At some later point in the timeline, Magneto was captured and sent to the same concentration camp where Storm, Colossus, Kate Pryde, Franklin Richards and Rachel Summers were imprisoned, and Wolverine ended up working solo to help liberate his former teammates. It is unclear what became of the other remaining X-Men and Emma Frost.
On the Earth visited by the reality-hopping Exiles in Exiles #21-22, the Legacy Virus had interacted with Warlock’s techno-organic transmode virus, creating an even deadlier disease. More than 75% of Earth’s population had been transformed into the techno-organic beings known as the Vi-Locks, super-powered individuals and average humans alike. That reality’s Emma Frost was among the few unturned people, and provided much-needed telepathic communication for the team of heroes since all radio communication was monitored by the Vi-Locks. Obviously, Emma was confined to a wheelchair, though the circumstances that led to this situation were never explained. Eventually, with the help of the Norse Gods, this reality could be fixed, and all infected people were cured.
The Emma Frost of the Ultimate universe can turn into a diamond shape, but she is no telepath. A former student and lover of Xavier, she parted ways with him because she felt his way was too violent and became a teacher herself. When the government grew wary of the X-Men they approached Frost to give them a viable alternative of young government-friendly mutants. The plan backfired, when Frost and her selected group were attacked by Sentinels and had to be rescued by the X-Men. As a result, Frost has somewhat patched things up with Xavier and may have a less rosy view of humans. She returned back to her own school in Chicago along with Cyclops' brother, Havok, promising to introduce him to the rest of her students, her "Hellions" as she called them.