Even in the depths of suffering, laughing is not something that comes easily to a person of intense emotions.

Literal

Extremely painful midst [even in-にも], laugh [topic-は], emotions [possessive-の] intense person [for-には] easy can-do thing [copula-ではない].

A complex, literary sentence. さなか means 'in the midst of.' 容易にできることではない means 'is not something easily done.' 感情の激しい人 is a relative clause modifying 人: 'a person whose emotions are intense.' The sentence reads like a philosophical observation.