Fraying Sanity has enchant player, so you can target any player, including yourself, as you cast it, and it can enchant any player, including its controller, while it's on the battlefield (C.R. 114.1b, 102.1, 702.5a, 702.5d). This applies to Fraying Sanity as it does to any other Aura or Aura spell with "enchant player".
Self curse