The phrase "All we need" suggests that, in the speaker's view, everything necessary for happiness, support, and fulfillment can be found within the relationship itself. It implies that material possessions or external factors pale in comparison to the significance of their connection.
The phrase "each other" underscores the idea that the mutual presence and support of both individuals are what truly matter. It reflects a sense of partnership, unity, and interdependence, where both parties contribute to each other's well-being.
In essence, this statement conveys the notion that the strength and depth of their relationship are so profound that it encompasses all they require for a fulfilling and contented life. It celebrates the beauty of love and companionship, where the presence and support of a beloved partner are the most valuable treasures one can possess.