The desire for freedom and the fear of confinement are in keeping with the other themes in Breakfast at Tiffany's. The need for freedom compels characters to act in strange ways in order to protect their independence, and they react just as strongly when they experience an impending sense of confinement. The desire for freedom also prevents some characters from allowing others to get too close, for fear that these others will then have some power over them. Some characters can't even look at literal tools of confinement like cages because of what these things represent.
There's no such thing as freedom in the novel. We just see the illusion of freedom.
The characters in the novel are truly free since most of them are unencumbered by concerns about other people. Their self-involvement represents true freedom.