Because unlimited feelings and desires arise within Krsna, as the best lover and the hero of all women He is sometimes dhirodatta (grave and gentle), sometimes dhira-santa (peaceful and forbearing), sometimes dhira-lalita (carefree and jovial), and sometimes dhiroddhata (proud and restless). He is all of these at the same time, and when there is the necessity for only one of these moods, He manifests that specific one.
In the same way, Srimati Radhika manifests whatever mood is necessary, sometimes becoming dhira (grave), sometimes manani (pouting), and sometimes daksina (clever). As the crown-jewel and very embodiment of the three hundred and sixty varieties of heroines, She relishes the sweetness of Krsna to the utmost. Because She can manifest all the qualities of all the varieties of heroines, She is known as ‘madanakhya- bhavati’.
While meeting with Krsna She experiences madana, and in separation from Him She experiences mohana. Sri Caitanya Mahaprabhu showed something of these elevated states of Hers to the world, and besides Him there has never been anyone in this world who could exhibit these things. However, when He was exhibiting these states, Srila Raya Ramananda and Srila Svarupa Damodara, due to being His intimate associates, could also relish something of them. Besides them no one else could comprehend these sentiments, but later Mahaprabhu invested the sakti to understand them directly into the heart of Srila Rupa Gosvami, saying, “He will manifest My bhava in this world through his writings.”
Bhakti Rasayana page 101 [CC-by-ND GVP]