pessimistic

US /ˌpes.əˈmɪs.tɪk/
UK /ˌpes.əˈmɪs.tɪk/
"pessimistic" picture
1.

tending to see the worst aspect of things or believe that the worst will happen

:
He has a very pessimistic outlook on life.
Don't be so pessimistic; things will get better.