A 2018 study (https://pubmed.ncbi.nlm.nih.gov/28703602/) found that suppressing negative emotions was more injurious to mental health than facing negative emotions head-on. The study found in the Journal of Personal and Social Psychology demonstrated that individuals who learned to accept negative emotions rather than judge them had more positive outcomes.
Lesson learned . . . just having a positive attitude may not yield the “Polyanna Effect” that one might hope.