With All Due Respect

What does with all due respect actually quantify? To exactly how much, if any respect does the speaker consider to be all that is due?

A recent and very much admired friend of ours just “respectfully” told us that she no longer wants to continue our friendship. No reason was stated.

We knew she intended to withdraw for a time. We feel somewhat heartbroken, but also confused.

A good friend is rare. A long-term friend is rare. A long-term good friend is a miracle.

We are very blessed.

Many thanks to our loving, if non-existent God, with a small fraction of the respect due.