"Oh, I don't talk about Jack and me. Some things are too good to share"

This quote by Lara Flynn Boyle suggests that the speaker and Jack have an unique relationship that is too valuable to be shown others. It indicates that the speaker values the relationship and wants to keep it private. It could likewise mean that the speaker is aware of the fragility of the relationship and does not wish to risk it by speaking about it. The quote might also be analyzed as the speaker wishing to protect the relationship from the judgement of others. It could be that the speaker knows the potential criticism that could originate from discussing the relationship and wants to prevent it. Whatever the factor, the quote suggests that the speaker values the relationship and wishes to keep it personal.