She becomes pregnant with Sean 's child .
When she begins a sexual relationship with Sean , Cathy reveals that she has always found Rebecca to be selfish and a bad friend , which serves as a wake - up call and leads to the end of the romance .
Cathy becomes pregnant with Sean 's child .
When she begins a sexual relationship with Sean , Cathy reveals that she has always found Rebecca to be selfish and a bad friend , which serves as a wake - up call and leads to the end of the romance .