Glass-Half-Full Meaning

(idiomatic, of a person) optimistic

Example: 2008, Megan Frost, Common Sense of a Different Kind: Matter-Of-Fact Thoughts on Women and Dating
  Normally she is an extremely positive, glass half-full sort of girl, someone who can find the silver lining in any situation. However, when it came to her breakup, she refused to see the many positive things that could come from it...