The Trinity, one God being three who relate to each other, seems paradoxical, prima facie, but perhaps it is only realistic (cf. how chemistry, as it became more realistic than alchemy, turned into a far stranger quantum mechanics). Let us presume that God created us, and the world around us, ex nihilo. Could He have incarnated as one of us? Well, He is presumably omnipotent; and perhaps we are essentially spirits, currently limited by our incarnation in human brains (with which we interact quantum mechanically), and perhaps God is also Spirit (who made us in His image).
......And an obvious way for us to think of creation ex nihilo is by analogy with the way we dream. When one dreams there is the creator of the dream (i.e. oneself), and the character in the dream whose point of view one has (i.e. oneself), and all the other stuff, which is not real but which corresponds (in God's creation) to us and the world around us. This is not supposed to be a very accurate model of divine incarnation; but if the other characters in one's dream were aware (as they obviously could not be) then they would naturally perceive one as a character with special powers and centrality, identified with and yet different to the creator of everything in the dream (including that special character's appearance), most strangely including themselves (which is where the analogy most obviously breaks down, but which may be where the Holy Ghost comes in).
......And quite generally perception (e.g. of a tree) seems to involve phenomena (e.g. green leaves) that are objectified (as what 'green leaves' refers to) in a rather paradoxical way (i.e. the problem of perception). Even when it is a perception of other people, so that we have a relatively direct knowledge of the kind of object, there is still an obvious distinction between how they seem to us and who they really are. And note that if there is a God then Idealism is not especially unrealistic. The connection between how something looks and what it is really like is made on the basis of wide experience and wise conjecture; and if the creator of everything else ex nihilo did incarnate as one of us, He might well be perceived by us as something more like a Trinity than not.