"Only One Heart" is a heartfelt and emotional song by Jimmy Nail. It revolves around a person desperately wanting to keep their loved one from leaving them, despite knowing it may not be possible. The lyrics express the singer's deep love and longing for their partner, acknowledging that they have loved them for a long time. However, they also understand that love alone may not be enough to make them stay. The song portrays the singer as trying to cope with the impending heartbreak. They struggle to find the right words to make their partner change their mind but ultimately realize that they cannot control their decision to leave. The lyrics suggest that the singer is willing to do anything, even pay any price, to make their loved one stay. In the verses, the singer describes their attempts to find solace in sleep, but they find sleep elusive as their thoughts are filled with their partner. They pray to God to help them cope and prevent themselves from dreaming, afraid of facing the reality of their impending separation. The chorus emphasizes the pain and confusion caused by the breakup. The singer questions why their heart has been shattered and wonders why people are created with only one heart. They highlight the uniqueness and preciousness of the heart they have given to their loved one, expressing their disbelief and sadness at the breakup. Overall, "Only One Heart" conveys the raw emotions of love, loss, and the struggle to accept the end of a relationship. The song beautifully captures the longing and vulnerability one feels when faced with heartbreak and the poignant question of why people are destined to have only one heart.