What is the meaning for a roller coaster in Ronan Keating song lyrics?

The roller coaster in Ronan Keating's song lyrics often represents a metaphor for an intense relationship. The ups and downs of a rollercoaster can symbolize the highs and lows of a relationship, with the thrill and excitement contrasted against moments of fear and uncertainty. The song may be about how his relationship is not always easy and fun, and sometimes takes him to unexpected places. The roller coaster may represent how the relationship is always changing, and how he never knows what will happen next.