Often, one person makes a choice. For example, in some stories, the female lead chooses the guy who she realizes truly loves her and has her best interests at heart.
In some modern love triangle stories, it might end with all three realizing they are better off as friends. They come to understand that the romantic feelings were more of a confusion or a passing phase. It's a more open - ended and less dramatic way compared to the traditional endings.
Often, one person in the triangle is left heartbroken. For example, in 'Romeo and Juliet', Paris is left out as Romeo and Juliet pursue their love and ultimately die together. In some cases, the main character realizes who they truly love and choose that person. Like in 'Pride and Prejudice' Elizabeth chooses Darcy in the end.
Often, one person in the love triangle ends up with the main character they are meant to be with. For example, in 'Inuyasha', Inuyasha finally chooses Kagome over Kikyo. Another way is that the character in the middle realizes they don't have romantic feelings for either of the other two in the triangle and decides to be alone or just be friends, like in some less - common storylines.
They often end with one person making a choice. For example, the person at the center of the triangle decides to be with one of the suitors. Or it could end with all parties realizing it's too complicated and walking away.
They can end with one person making a selfless choice. For example, one of the people in the triangle realizes that their friend really loves the person more and steps aside. Another way is that the person who is the center of the triangle chooses one of the two. Sometimes it's a happy ending where the couple stays together, and the other person moves on.
Often, the protagonist makes a clear choice between the two love interests. For example, in some novels, the girl might realize that one guy has been there for her all along and truly understands her, so she chooses him over the other.
Often, the heroine ends up with the 'right' man. For example, in many cases, the man who truly understands her and has a deeper connection wins her heart in the end. So, if there's a rakish character involved in the love triangle, she usually chooses the more honorable and loving one.
Some love stories end in a more bittersweet way. The couple may part ways, but they have grown and learned from the relationship. They might still have love for each other, but they realize that they are better off apart for various reasons, such as different life goals or personal growth directions.
They often end happily, with the couple getting together. For example, in many classic romances, the two lovers overcome all the difficulties and start a new life together.
Some animation love stories end bittersweetly. In 'A Silent Voice', Shoya and Shoko's relationship is complex. They have a history of bullying and redemption. In the end, while they don't have a traditional 'happily ever after' in the sense of a perfect relationship, they have a new beginning of understanding and connection, which is a different kind of positive ending.
Western love stories often have diverse endings. For example, in 'Sense and Sensibility', the sisters find love in the end, which is a positive conclusion. However, in 'Gone with the Wind', Scarlett loses Rhett in the end, which is a rather sad ending. There are also stories where the ending is open - ended, leaving the readers to imagine what might happen to the lovers, like in some modern romantic novels.