Dave Clancey has posted an excellent summary of John Webster's take on God's aseity. Prof. John Wesbter is Chair of Systematic Theology at the King's College, Aberdeen, Scotland.
God's aseity is his independence. He doesn't need us; we need him. Usually, this independence has been seen as a necessary implication of him as creator. Creation needs a creator outside of itself.
But, if I understand Dave's summary correctly, Webster rightly sees this as being too impersonal. Webster reconceptualises God's aseity to be an outworking of his triune life. God is independent of us, not merely because he is the foundation of the cosmos, but becuase he, as Trinity, has life in himself. The Father, Son and Spirit give life to each other, and therefore stand in need of nothing outside of each other. Creation and redemption are the outflowing of this intra-Trinitarian life.