Because all her older sisters married very early, Auguste became by 1793 in the primary caretaker of her parents, and a particular support to her ailing father.
The union was childless and lasted only 18 months until Frederick Louis' death on 29 November 1819. She was a devoted stepmother for her husband's children, taking responsibility for their upbringing and education. She developed a particularly close relationship with her stepdaughter Helene, second child and only daughter of her cousin Caroline Louise.
Auguste, who never remarried, remained in Mecklenburg-Schwerin for the rest of her life, dying in Ludwigslust aged 94. She was buried at the Helena Paulovna Mausoleum, next to her husband and his two previous wives.