An ounce of prevention is also worth a pound of cure. More important than investing resources into helping those with mental illness is preventing people from developing mental illness in the first place.

Traumatic experiences like you mentioned can be reduced by better education about what to look for in healthy relationships, or providing accessible resources to catch issues early before they become major issues. Other, more subtle, issues like neglect, poor home life (often due ti poverty, difficult family situation, etc.) would require more pervasive changes to address, but if prevent issues in society on the back end due to reduced incidence of mental illness, not to mention the improvement in quality of life for those affected, we should seriously consider those options.