Before 1032 Gruoch was married to Gille Coemgáin mac Maíl Brigti, Mormaer of Moray, with whom she had at least one son, Lulach mac Gille Coemgáin, later King of Scots. Gille Coemgáin was killed in 1032, burned in a hall with fifty of his men. Gruoch's second marriage was to King Mac Bethad, again the date is unrecorded. No children of this marriage are known.
Gruoch is named with Boite and also with Mac Bethad in charters endowing the culdee monastery at Loch Leven. The date of her death is not known.
She served as the model for the character Lady Macbeth in William Shakespeare's play Macbeth. A slightly more accurate version of Gruoch appeared in the animated television series Gargoyles.