Offer Sims various ways to deal with their emotional distress:

If you or someone you know is struggling, help is available. You can reach out to: Suicide & Crisis Lifeline

Implement storylines or scenarios where Sims overcome stigma related to mental health. For example, a Sim might initially be ashamed of their struggles but eventually opens up to friends or family, leading to positive outcomes.

Many players seek to move beyond the idealistic "perfect life" of a standard Sims save. This has led to the popularity of "Life Drama" or "Realism" mods. These creations often include: Mental Health Systems