Once an elf engages in reciprocated love with someone, that's it. If he cannot be with that person he will lose the will to live, die, and become a forever-shade in the Halls of Mandos. Elves do not move on.
Unlike Men and Dwarves, Elves are immortal, though they can be killed in battle. If so, their souls go to the Halls of Mandos in Aman. After a long life in Middle-earth, Elves yearn for the Earthly Paradise of Valinor, and can sail there from the Grey Havens.
In the books and Legendarium, there examples of full-blooded elves (ex. Arwen and Luthien) who willingly sacrifice their immortality to spend a mortal lifetime with the humans they love.
Arwen reciprocated Aragorn's love, and on the mound of Cerin Amroth they committed themselves to marrying each other. In making that choice, Arwen gave up the Elvish immortality available to her as a daughter of Elrond, and agreed to remain in Middle-earth instead of travelling to the Undying Lands.
They can't die by age, but they can die by the sword or grief. According to Tolkien, once an Elf becomes an adult, they stop getting older. They are also less vulnerable against physical damage, but they aren't immortal. The lives of Elves only endure as the world endures.
Elves follow mammalian reproduction, with a gestation period of 8 months.
Elf Traits
An elf typically claims adulthood and an adult name around the age of 100 and can live to be 750 years old. Alignment: Elves love freedom, variety, and self- expression, so they lean strongly toward the gentler aspects of chaos.
While the date of Legolas's birth is unknown, he was likely born sometime after his grandfather was killed and his father took over the rule of the Woodland Realm. Like all Elves, Legolas is immortal. Elves do not die by natural causes; however, they can be killed in battle.
However, he does not possess the ability to live forever, and he cannot choose to be mortal or immortal like Arwen, the half-Elf he loves and eventually claims as his wife. Because Aragorn is mortal and Arwen chose to remain in Gondor and become mortal, their son, Eldarion, is mortal as well, despite his Elven lineage.
He had a twin brother
Partially this was due to the unique situation of their ancestry: because of the complications of being descendants of marriages between mortals and immortals, Elrond and his brother Elros were given the choice of their own fates, to be mortal with humanity or immortal with the elves.
Pretty much just like humans, since they can inter-breed, though elves seem to only have children when they want them, which means: A) They have fantastic contraceptives. B) They only have sex to procreate.
When elves die, their spirits travel to the Halls, where they rest for a time as disembodied shades. Most of them are then returned to corporeal form and rejoin all the other elves living in Valinor.
Elrond has only Half-Elf, and he was once given the choice to be counted among Man or Elves. When he chose to be counted as Elven kind, he was then given immortality. Because Arwen is Elrond's daughter and also Half-Elf, she too has the choice to be a mortal woman or an immortal Elf.
Arwen's response is that there is no ship to take her to the Undying Lands. Anyway, she made her choice a long time ago. Her response would seem to suggest that she is fully mortal, and therefore unable to go to the Undying Lands unless a special circumstance presented itself.
The Birth of an Elf Is Rare in Middle-earth
And it's exactly that: a choice. Unlike other races of Middle-earth, casual intercourse was not enough to conceive a child because, for Elves, it was a far more conscious effort that required, as Tolkien put it, a "share and strength of their being, in mind and in body."
In Middle-earth, half-elves are the children of Elves and Men, and can choose either Elvish immortality or the mortal life of Men. The elf-maidens Lúthien and Arwen in Tolkien's works both chose mortality to be with the Men that they loved.
The Gift of an Arwen Evenstar Necklace
Princess Arwen Evenstar gave her beautiful necklace to Aragon to pledge her eternal love to him. This special gift from an immortal elf to a mortal man symbolized Arwen's decision to forsake her immortality to be with the person she truly loves.
And Tolkein himself confirms this in his own private letters, where he makes it clear that Frodo and his friend Sam (who is also eventually granted a place in Valinor) would always be mere mortals and would eventually succumb to death even if they were to remain in The Undying Lands.
In the year 121 of the Fourth Age, after Aragorn's death, Arwen died of a broken heart at Cerin Amroth in Lórien, and was buried there one year after the death of Aragorn, to whom she had been wedded for 122 years. She was 2901 years old.
What is Legolas syndrome? The actor is suffering from Legolas Syndrome — where you accidentally get cast into a role that suits you far more than your real-life looks, leaving you with a tricky predicament after the wrap party.
Immortality: Like other elves, Galadriel is immortal, meaning she can never die or grow sick or old. However, she is able to be killed if she fell in battle.
Legolas never marries. The closest he gets is spending the rest of his life, as far as we know, with Gimli; they travel around Middle Earth for decades together, and eventually Gimli is given special dispensation to travel to the Undying Lands with his "friend" Legolas—the only dwarf ever to do so.
An elf typically claims adulthood and an adult name around the age of 100 and can live to be 750 years old. Elves take their time doing things because of their long life span. So to them 100 years feels like what 20 years feels like to a Human.
Elves typically reach maturity around the same age as humans, however their lifespan is infinite. How old are Santa's elves? Santa's elves are a variety of ages from 25 – 2025.
The calculation I use to help players understand the maturity differences is to convert all other ages into the human equivalent. So a 16 year old half-elf is approximately 8.4 years old in human maturity terms. A 16 year old elf would be 3.8 years.