expression, i-adjective
can't help but do; feel compelled to
Expresses an uncontrollable urge or emotional compulsion to do something. Attaches to the negative stem of a verb (V-ないではいられない). Often used for strong feelings, curiosity, or laughter. Similar to ずにはいられない, but ないではいられない is slightly more colloquial.
See also: ずにはいられない
その話を聞いて、笑わないではいられなかった。
Hearing that story, I couldn't help but laugh.
彼女のことが気になって
I'm so curious about her that I can't help but contact her.