The mystics always go to the Trinitarian level because here God is a verb more than a noun, God is a flow more than a substance, God is an experience more than an old man sitting on a throne. And we are inside that flow of love. Julian writes:
Greatly ought we to rejoice that God dwells in our soul; and more greatly ought we to rejoice that our soul dwells in God. Our soul is created to be God’s dwelling place, and the dwelling of our soul is God. . . . [This is what some call inter-being.] It is a great understanding to see and know inwardly that God, who is our creator, dwells in our soul, and it is a far greater understanding to see and know inwardly that our soul, which is created, dwells in God in substance, of which substance, through God, we are what we are. [We share in the same substantial, ontological, and metaphysical unity.] And I saw no difference between God and our substance, but, as it were, all God; and still my understanding accepted that our substance is in God. 
.. She is not a pantheist; she is not saying everything is God. She is saying everything is in God and God is in everything— which is panentheism.