He has been 'struggling' with the problem of how to keep good workers from leaving.
She is 'struggling' with her health. [=she is having problems with her health]
She was 'struggling' with the door. [=trying to open the door]
(..) the current is weak. The kayaker can paddle against it and get away. But closer to the waterfall, the current is stronger, And the kayaker struggles to escape. The edge of the waterfall is like the edge of a black hole. No matter how strong the kayaker is, he's going down. (..)2010 TvShow: How the Universe Works Title: Black Holes Season: 1 Episode 2