optimist
noun /ˈɒptɪmɪst/
  /ˈɑːptɪmɪst/
 - a person who always expects good things to happen or things to be successful
- I'm an eternal optimist—I'm sure things will get better.
 - He’s an incurable optimist.
 - Pete, ever the optimist, said things were bound to improve.
 
Oxford Collocations Dictionaryadjective- eternal
 - incurable
 - cockeyed
 - …
 
- ever the optimist