The love triangle is a key element in the plot of this classic work. Let us remember that it starts of with the relationship that Eustacia and Wildeve have enjoyed, and how this relationship is what makes Wildeve decide that he will not marry Thomasina as planned, and will pursue his relationship with Eustacia. However, this only lasts until Clym Yeobright returns. He is a fascinating figure for Eustacia, and seems to represent all of her hopes of leaving her homeland and enjoying a much more exciting and wealthy life. She therefore begins to draw him in, and eventually they marry.
However, fate does not have a happy ending in store for Eustacia. Having married Clym with the hope of wanting to leave and visit and travel other parts of the world and enjoy a good life and fulfill the potential she feels she has always had, her husband settles to become a furze cutter, which is exactly the kind of fate that Eustacia wanted to avoid. What is more tragic is that Wildeve has become rich and offers exactly the kind of escape and wealth that Eustacia desires. However, she resists starting a relationship with Wildeve, but tragically they are seen together, and Clym finds out, resulting in their separation.
Finally, we have the tragic ending of the story. Eustacia plans to escape, but finds a different kind of escape. Trapped by circumstances and forces beyond her control, she jumps into a river and drowns herself. Clym and Wildeve both jump after her to rescue her, and Wildeve dies in the attempt too. Only Clym survives, being left to carry out his life sad and alone.