Analysis:

This quatrain by Saadi Shirazi is a heartfelt expression of love and longing. Let's delve into its deeper meanings:

Dependence on the Beloved: The poet expresses an inability to find peace or joy without their beloved. Their happiness is entirely dependent on the other person.
The Beauty of the Beloved: The comparison of the beloved's face to a rose highlights their beauty and the poet's intense admiration.
The Pain of Unrequited Love: The last line suggests that the love is unrequited. While the poet has tried to forget their beloved, it is the beloved who continues to dwell on the poet.
Irony and Resignation: There's a touch of irony in the final line. The poet has sought relief by forgetting, but it seems that their beloved's memory is more persistent. This suggests a sense of resignation to their unrequited love.

Themes:

Unrequited love: The central theme is the pain of unrequited love.
Dependence: The poet's happiness is entirely dependent on the other person.
Beauty and longing: The poet's longing is intensified by the beauty of their beloved.
Irony and resignation: The final line suggests a sense of resignation to the inevitability of their unrequited love.

Deeper Meaning:

This quatrain is a poignant exploration of the human experience of love and loss. It captures the feeling of being completely consumed by love and the pain that comes with unrequited affection. The poet's resignation to their fate suggests a deep understanding of the complexities of human emotions.

This quatrain is a timeless expression of love and longing. It reminds us of the power of love to both bring joy and cause pain.