First, she glorifies herself. This implies pride, even to the point of arrogance. Jeremiah 51:41 is used in relation to ancient Babylon, but it applies to modern Babylon as God uses it here in Revelation 18. Jeremiah writes:
How is Sheshach [a biblical code name for Babylon] taken! And how is the praise of the whole earth surprised! How is Babylon become an astonishment among the nations!
This refers to the fall of Babylon. When Jeremiah wrote this, they were so powerful as a nation that nobody wanted to deal with Babylon as an enemy. He calls her "the praise of the nations." This means, essentially, "the greatest of the nations." Everybody praises Babylon as the greatest of the nations on earth. God applies this to Babylon in Revelation 18. It is something implied, not directly stated. However, even Babylon "has glorified herself."
Second, "she has lived deliciously" or "she has lived luxuriously, extravagantly, lustfully, unrestrainedly." The woman is the very apex of luxury on earth. This phrase indicates satiety, that is, over-indulgence, super-abundance, the state of having too much.
Third, she says, to magnify these, "I sit as a queen, and am no widow, and shall see no sorrow." "Nobody's going to bother with me. I'll never know any sorrow." Taken together, there is in her an avoidance of suffering, an unwillingness to sacrifice, and it indicates a rather "in your face," cocky superiority. Interestingly, an avoidance of suffering, the unwillingness to sacrifice, inevitably produces compromise with law and conscience.
In this one verse, a nation is portrayed as proud to the point of arrogance, self-confident in its security, thinking that it has produced its power by its own means, and living extravagantly relative to the rest of the world, as it seeks immediate gratification while failing to discipline itself to conform to a set standard.