Actually, there is something wrong with your mood. First of all, you miss your dead relatives very much, and you always hope that the last thing can help him complete it successfully. So you unconsciously expect a lot from yourself in this matter, but subconsciously you always feel that you have not done enough, worrying about this and that for no reason, fearing that you have done something inappropriate, and having a sense of guilt and anxiety for no reason, so you will have such a dream (the embarrassment of public sacrifice is obviously comprehensive, but it always feels lacking).
At the end of the dream, you have a good wish that the old man can rest in peace and live freely and happily in another world. Therefore, in fact, "ashes mixed with sea water and sand in a glass bottle" is actually a good metaphor, indicating that he has rested, and the last material skin has returned to nature and belongs to the earth, so you don't have to feel sad.