There are no two enemies-to-lovers relationships alike. Enemies-to-lovers is a common narrative, but it also has depth and subtlety that goes beyond two people on opposing sides falling in love. The thing to remember about tropes and fiction is that they are just that: fiction. What may seem like reality to one person could be completely different for all others.
So yes, enemies can become lovers. It all depends on the story and what kind of relationship each character is looking for at the end of it. There are many stories out there where this trope is used as a way to resolve conflict or move the plot forward. Or not - see what works for you!
Enemies-to-lovers is a very common theme in literature. Here are just a few examples:
In Shakespeare's Romeo and Juliet, the feuding families become friends after Romeo dies fighting for his country.
In George Bernard Shaw's pre-revolutionary play Arms and the Man, everyone is an arms dealer until one girl shows up who wants to change everything about the business.
In John Steinbeck's novel The Grapes of Wrath, the Joads travel from California to Oklahoma, where they hope to find work and escape the poverty caused by the decline of the farming industry.
The "enemies to lovers" cliché occurs when two characters begin as foes and wind up in a romantic connection throughout the course of a book or series. This partnership serves as a spark for their relationship to go from "enemies" to something more. Often, these pairs end up becoming friends after they leave each other at the story's conclusion.
Older examples of this theme can be found in classical literature. The enemy of my enemy is my friend philosophy is well known through many ancient cultures including China, India, and Greece. It also appears in modern works such as Go Ask Alice by Anonymous and I Hate You, Don't Leave Me by Elizabeth Mitchell. Enemies to lovers stories really take off in literature with Shakespeare's Romeo and Juliet. Here, the young lovers are enemies who fight until they fall in love then become rivals once they are able to kill one another's families. Their story ends with both victims of a deadly poison.
In today's world, this theme continues to appear in books for entertainment purposes only. There are two movies that come to mind that fit this category: Twilight and The Notebook. In Twilight, teenage vampires Bella Swan and Edward Cullen are enemies who fight until she saves him from being killed by her fellow students. They then fall in love and have children together despite living centuries apart.
It's a common theme, especially in science fiction and fantasy works. An enemy group becomes involved with an ally group through some sort of conflict or adversarial relationship, and then they start falling in love with each other.
For example, in Star Wars, the Empire has taken over the galaxy, but it turns out that many of its leaders were members of the Rebel Alliance before they were captured and forced to serve the Empire. Similarly, the Jedi were an ancient order of warriors who were responsible for maintaining peace and justice in the galaxy until they were destroyed by the Sith.
Even characters within the same story or movie can be enemies one moment and friends the next. This is called "morality play" or "moral ground". In Shakespearean drama, all characters are given a background history for each scene they appear in, so that the audience can understand why certain actions are deemed acceptable or not acceptable by society at large.
In literature, enemies can become allies through a process called "bonding", which means that they come to respect and like each other despite their differences.
Do you want to know why I enjoy the "enemies to friends to lovers" cliche so much? Because such a connection necessitates respect. They begin by disliking one other, but they must work together until they discover they have something in common, at which point they develop respect, which gradually grows into love.
It's simple and pure. There is no room for manipulation in an enemy-to-friend-to-lover relationship. They may dislike you at first, but that doesn't last long once they realize they can trust you with their secrets and vices. Eventually, they will come to love you back.
The classic example of this theme is Romeo and Juliet. They are enemies at first, but then she helps him out of a predicament, and he becomes her friend. Once they realize they can trust each other, they grow closer to one another, until finally they fall in love.
This type of story is perfect for film or television because it gives the storywriter plenty of room to play around with. The only requirement is that whatever happens to the enemies must lead to the friends partway through the story or movie.
For example, in Shakespeare's Romeo and Juliet there are three enemies who become friends at the end: Tybalt, Mercutio, and Romeo. Then there are two friends who become lovers: Romeo and Juliet.