(Note: this is a collection of the meanings attributed to the cards by some occultists in the past centuries. It does not reflect my own study or opinion of the cards. It is only meant as a quick comparative reference as I develop my own take.)

Paul Foster Case (and Ann Davies)

The Five of Cups is the first decanate of Scorpio, ruled by Mars, time period October 22 to October 31.
Well-Dignified: strength, power to do; ability to introduce needed changes and let go of relationships, prejudices and false ideas that are hindering spiritual progress.
lll-Dignified: loss in pleasure, vain regret, disappointment, sorrow and loss of those things which have been much desired; treachery, deceit; unexpected troubles and anxieties; disappointments in love, broken engagements, broken friendships.
(Note: These sorrows and disappointments, as indicated by the Five of Cups, lll Dignified, are often the necessary destruction before the beginning of a new and greater expansion and growth in the life of the Querent, depending on his basic understanding and evolutionary level.)
Keyword: Defeated desire.
(From the Oracle of Tarot course)

A. E. Waite

A dark, cloaked figure, looking sideways at three prone cups two others stand upright behind him; a bridge is in the background, leading to a small keep or holding. Divanatory Meanings: It is a card of loss, but something remains over; three have been taken, but two are left; it is a card of inheritance, patrimony, transmission, but not corresponding to expectations; with some interpreters it is a card of marriage, but not without bitterness or frustration. Reversed: News, alliances, affinity, consanguinity, ancestry, return, false projects.
(From The Pictorial Key to the Tarot)

Aleister Crowley

 […] the Five of Cups is called Disappointment, as is only natural, because Fire delights in superabundant energy, whereas the water of Pleasure is naturally placid, and any disturbance of ease can only be regarded as misfortune.

This card is ruled by Geburah in the suit of Water. Geburah being fiery, there is a natural antipathy. Hence arises the idea of disturbance, just when least expected, in a time of ease.

The attribution is also to Mars in Scorpio, which is his own house; and Mars is the manifestation on the lowest plane of Geburah, while Scorpio, in its worst aspect, suggests the putrefying power of Water. Yet the powerful male influences do not show actual decay, only the beginning of destruction; hence, the anticipated pleasure is frustrated. The Lotuses have their petals torn by fiery winds; the sea is arid and stagnant, a dead sea, like a “chott” in North Africa. No water flows into the cups.

Moreover, these cups are arranged in the form of an inverted pentagram, symbolizing the triumph of matter over spirit.

Mars in Scorpio, moreover, is the attribution of the Geomantic figure Rubeus. This is of such evil omen that certain schools of Geomancy destroy the Map, and postpone the question for two hours or more, when Rubeus appears in the Ascendant. Its meaning is to be studied in the “Handbook of Geomancy” (Equinox Vol. I, No.2).
(From The Book of Thoth)

Golden Dawn’s Book T

A WHITE Radiating Angelic Hand, holding lotuses or water-lilies, of which the flowers are falling right and left. Leaves only, and no buds, surmount them. These lotus stems ascend between the cups in the manner of a fountain, but no water flows therefrom; neither is there water in any of the cups, which are somewhat of the shape of the magical instrument of the Zelator Adeptus Minor. Above and below are the symbols of Mars and Scorpio for the Decan.

Death, or end of pleasure: disappointment, sorrow and loss in those things from which pleasure is expected. Sadness, treachery, deceit; ill-will, detraction; charity and kindness ill requited; all kinds of anxieties and troubles from unsuspected and unexpected sources.
Geburah of HB:H (Disappointment in love, marriage broken off, unkindness of a
friend; loss of friendship).
Herein rule HB:LVVYH and HB:PHLYH.

Etteilla

Legacy
Upright. This card, in its natural position, means, as far as the medicine of the spirit is concerned: Inheritance, Succession, Bequest, Gift, Donation, Endowment, Estate, Transmission, Will. – Tradition, Resolution [=Decision]. – Kabbalah.
Reversed. Consanguinity, Blood, Family, Avi, Ancestors, Father, Mother, Brother, Sister, Uncle, Aunt, Cousin, Cousin. – Filiation, Extraction, Race, Lineage, Alliance. – Affinity, Attachment, Relationship, Ties.

MQS