Robert Sternberg's Triangular Theory of Love
In this 2004 theory, Robert Sternberg proposed that love could be broken down into three parts: intimacy, passion, and commitment.
Intimacy
Closeness, supporting one another, sharing with one another, and feeling loved.
Passion
Feelings of sexual arousal and attraction, and euphoria. This is what drives two individuals together.
Commitment
The desire to remain loyal to another person and stay in a long-term relationship.