Ice Rink Symbol
After Jenny passes away, Oliver goes to the outdoor ice rink, because it is a symbol of the last time that they were together before Jenny went into the hospital. It symbolizes their love and their relationship, and the fact that Oliver will always be able to find her even though she is not physically with him anymore.
Paris Symbol
To Oliver, Paris is a symbol of Jenny's dreams, and the fact that she gave them up for him which makes him feel extremely guilty. She chose not to go to Paris to further her musical studies, instead choosing to stay with him and support him through law school.
Unconditional Love Motif
Of course, a film called Love Story has the theme of love at its core; however, the motif of unconditional love is also present throughout. It begins with an example of what unconditional love is not - Oliver's parents do not approve of his relationship with Jenny because she is not what they pictured for their son - and so they disown him. This is not unconditional love.
When Jenny tells Oliver that "love is never having to say you are sorry" she is also teaching him about unconditional love, because she is letting him know that even when he behaves poorly she will still love him. This is the same thing that Oliver says to his father after he apologizes for causing their estrangement, indicating that Oliver, too, loves his parents unconditionally even though they have acted badly.
Music Motif
Throughout the film there is a music motif largely because Jenny is a music student. Her loves - other than Oliver - are composers, and her dreams all revolve around becoming a professional musician. Music is also what she give up in order to be with Oliver.
Music Symbol
Music is also a symbol of Jenny, especially for Oliver, who sums her up by saying that she "loved Bach, Mozart, The Beatles - and me." As a music student she wants to become a professional musician, and also plans on going to Paris to further this goal;music is what she gives up to be with Oliver, and this is a symbol to him of the great weight of responsibility he carries by being loved this much by Jenny.
