Complex sentence: This personality seem to be the only one who want to David to be happy so she made the Age of X reality where David would be seen as hero and took the form of Moira and become his "mother" in this reality.
Split into simpler sentences: This personality seemed to be the only one that wanted David to be happy so she made the Age of X reality where David would be seen as a hero. She took the form of Moira and became his "mother" in this reality.