I think that Draka said it well in her post #22.
I think that Life is sacred. I think that Love is sacred. Experiences closely related to honoring Life and Love are sacred.
For me the idea of some "thing" being sacred does not rest in the thing itself, it is honoring the love and value that rests in or is represented by the thing.
I often use the term "scared texts" when referring to religious texts. I use that term even toward texts that I have no familiarity with. What I am referring to is that I honor the love and value that other people may have toward that text -- it is a term of respect for something that another person holds dear. It is the love that is being honored there.
One can respect another person's right to their love for something, and their beliefs, and not equate it with a requirement to have that exact same love or belief for oneself. That understanding, I think, comes from truly honoring one's own love and right to an individual understanding of life, which will contain differences of beliefs. With that understanding, one can easily extend the same respect to others.