Sophia Louise of Mecklenburg-Schwerin was born on 6 May 1685 as the daughter of Frederick, Duke of Mecklenburg-Grabow and Christina Wilhelmine of Hesse-Homburg. Not much is known of her youth. On 28 November 1708, she married Frederick I of Prussia as, his third wife. He was almost 30 years older than her. She had received no serious education, and she was introverted, not a good quality for a Queen. She was a religious woman, and she tried to convert her husband from Calvinism to the Lutheran faith. He was not amused by her efforts, and they fought often.
Sophia Louise’s mental health soon deteriorated. Once she frightened her husband when she believed she was the White Lady, or a ghost, and foretold his death. She became deeply depressed and was unable to perform her duties as Queen. Eventually, Frederick sent her back to her family. He died shortly after sending her away in 1713.
Sophie Louise spent the rest of her life in Grabow Castle and Schwerin Castle before dying in Schwerin Castle on 29 July 1735. She is buried in the Schelfkirche St. Nikolai in Schwerin.
I remember reading she ran into his room in her nightgown, he thought it was the ‘White Lady” telling him he would die. It shocked him into a heart attack, or something like that, & he died. In that scenario he could not have send her away before his death.
Walter Henry Nelson writes the above in “The Soldier Kings, The House of Hohenzollern”, page 58.