This is the danced opera "Onegin" by Pjotr I. Tshaykovski choreographi by John Cranko Stuttgart for Marcia Haydee and Richarrd Cragun 70 -80 in this years.

Well as David Hallberg says, it’s quite complex. There are four main characters: Tatjana, who loves Onegin. Olga, her sister, who loves Lenski, a poor student and nice guy. Lenski loves Olga. Onegin, Lenskis friend, loves only himself. Tatjana writes a letter to Onegin that she loves him. He makes fun of it and tears the letter and gives it back to Tatjana. Then he starts flirting with Olga. Lenski is furious and asks for a duel with Onegin. Lenski looses and gets shot to death. Tatjana marries someone else. So does Olga. Years later Onegin feels lonely and comes back and asks Tatjana for forgiveness. She throws him out, but when he is gone she cries. - The End- 🤷🏻‍♀️