to make (someone) realize (e.g. their mistake); to bring (something) home (to someone); to teach (someone) a lesson
自分の過ちを思い知らされた。
I was made to realize my own mistake.
厳しい現実を思い知らす出来事が起きた。
An incident occurred that brought home the harsh reality.
彼の冷たい態度が、自分の立場を思い知らせる結果となった。
His cold attitude ended up making me aware of my position.