Can you describe examples for each?
The latter is easier. My Demon Blood character Kira. Her powers, which in the lore are derived from demonic taint, mean she's incredibly strong. However she hates her powers because it's impossible to control. Especially with her lack of social awareness and skills. For instance a simple shove out of the way can result in flinging someone across the room. She gets more and more depressed and shit as she goes on, starting to give up hope that she can ever actually live a life beyond fighting.
The former is harder to explain exactly. It requires set up. Showing how strong the enemy is (or just how violent they are) and then showing how the characters opposing them, while strong, have to focus and use all their skill to overcome them. For instance thing I'm writing. The "good guy" character is fighting a demon. This is something he does somewhat often. And the demon isn't the strongest he's faced. And yet despite that, he has to push himself hard, use abilities that take a toll on his body, just to have a chance. And even then he fails to stop them from brutalizing several innocent people. He hides this from the main person he's protecting, and tries to pretend that things are okay, when inside he's slowly driving himself mad with guilt. Because he continues to try and save everyone and has tried for years. Despite how impossible that is.
More/less it's a "fighting a losing battle" thing.