2 parts Complete MatureSam has been struggling with depression since Stanford. Well, not really struggling. Excelling. He's been excelling at depression since Stanford, and it's only gotten worse since he started hunting again. Unfortunately, the relapses from John's death and Dean's trip to Hell were bad, but they had nothing on the downward spiral triggered by Sam starting the Apocalypse.
But Sam has never come clean before, and he isn't about to start. He's self-medicating, he's suppressing, and he's handling things in the Trademark Winchester Way. He can do this. He can totally do this.
Spoiler: No, he can't.
WARNING: Mentioned suicide attempts, suicidal ideation, and depression.