Diel Fin'al Thalas
Desperate to circumvent her fate and leave the place that holds her literal nightmares, Sylvanas Windrunner seeks out the powerful Jaina Proudmoore to form a contingency plan. However, with the introduction of the mourneblade and the reminder of her traumatic past, Sylvanas realizes the mage is her only true path to freedom and, despite Jaina's initial reservations, an uneasy alliance is formed. Unfortunately, the mistrust between them comes to a crux at the worst time, and in order to move forward Jaina suggests an old elven agreement that, unbeknownst to her, she has gravely misunderstood the intentions of.
or
Yet another marriage fic, except we're dealing with the Shadowlands mess and actually addressing Sylvanas' trauma.