I quite often draw the 5 of Cups and the 8 of Cups in my professional readings, and I'm struck by how similar yet different they are. Obviously, their corresponding numbers make up a large part of that: the Five is more chaotic and yearning, while the Eight is more coordinated, approaching completion in the Nine and considered a "strong" number because it represents a doubling of the stable and solid Fours (thus the Celtic meanings of "abundance" and "manifestation" that I came across in the DruidCraft Tarot book). Better, I guess, if an "abundance of dissatisfaction" is your cup of tea.
But both of the figures in these cards look despondent. That in the 5 of Cups seems lost in the throes of his despair, and doesn't notice (yet) that all is not lost. The one in the 8 of Cups seems to have given in to resignation, and is departing in decidedly low spirits. The former is morose, the latter seems more stoic but no less depressed. One is moaning loudly "Woe is me!" while the other seems resolutely silent and preoccupied.
I usually tell clients getting the 5 of Cups that they may have to leave a big chunk of their emotional investment behind, but they should salvage what they can of their self-esteem, pick up the two upright cups and get on across the bridge. I call it "taking the best and leaving the rest;" some emotional baggage will have to be cast off in order to move on. The bridge and the castle in the distance are compelling talking points in making this argument.
When the 8 of Cups comes up, I mention that the man has looked in the eight cups and wasn't satisfied with what he found. The gap in the array of cups can't be filled in the present circumstances, so he is starting off dejectedly over the hill in search of a ninth one, following the Moon (related to the number 9) and heading for the 9 of Cups. In that sense I see the 8 of Cups as transitional, offering a bitter brew that dispels the fantasies of the 7 of Cups but still "steering by the light of the Moon."
In the case of the 5 of Cups, all the man has to do is raise his head and turn around to see the way out. In the 8 of Cups, he has to make more of an effort, in more uncertain conditions and with unreliable illumination over rough terrain. Frankly, I don't see much hope in either one. The 5 of Cups looks more obsessive and the 8 of Cups more cynical, but neither one is in a happy place. At least the man in the 8 of Cups is moving ahead, however fatalistically; the one in the 5 of Cups is stuck in neutral until nudged out of his daze.
Note that I'm making these observations mostly from what I see in the images. I'm curious what other intuitive (not
book-based) insights you have about these cards.