Because his concubine wives kept plotting against her than he promoted that concubine. She said this life & problems belong to this bodies owner and wanted something that belong to her that she achieved for herself thats why she left!
She was thrown off the deep end right from the start every one hated & wanted her dead her husband his mother & all his wives. The wife he rewarded was the one that killed the mother of his son the real Queen she's just pretending to be her thats rough
Wait, so why are they not together ?