After beating the summoned boss in the Ritual Site, I used town portal to go back to the hall of elders, and then used the same, still active town portal, to return to the Ritual Site.
After returning, the NPCs (Maceth, Leyda and friends) who summoned the boss are standing there again with the same dialogue, even though they supposedly sacrificed themselves.
Certainly, story zones get reset upon leaving and re-entering; currently this is because of technical limitations. As Llama mentioned, this will be addressed with multiplayer is released. Thank you for the report.
