Form the scientific standpoint: There is nothing Astronomical that would explain this sighting, to put it simply. It may be meteorological but it is verrry unlikely. Your description is similar to a phenomena called a sun-dog but the stated time of day and duration makes that impossible. As for the GreenWitches' ...the Great Diamond of Virgo... this is wayyy past absurd. I have been active in amateur astronomy for decades and have never heard of this. Of the four stars named only Spica is even in the constellation Virgo.
Greeny: Try breaking the Prozac in half next time.
The description is also ridiculous. These stars
are visible at the same time in the same sky. They are
not only visible in spring and are best placed for observation in the fall. But to say they are so bright and so close as to appear as a solid object is laughable. They are some of the brightest stars in the night sky, but the full moon (aprox. mag. -13) is more than 10,000 times brighter than any of these stars (aprox. Mags. 0 to 1). The separation between Arcturus and Spica, for example, is 32 degrees! For comparison the full moon is about seven tenths of a degree across. In other words they are so "close" over 35 full moons would fit between these two stars. The others have similar separations. That ANYONE would see them as a UFO only tells you something of what is in the observer's head NOT what is in the observer's sky.
If it is something else then it is unimportant as to what it was, where it came from, who "sent" it, etc. from an external perspective. What is (or may be) more important to you is what, if anything, it signifies to you. And what, if anything you should do, think, or feel based on the experience. But this analysis must come from inside of, and can only be done by, you. Hope that helps.
A true fact about the constellation Virgo: It is known as "The Realm of Galaxies". Virgo contains the nearest major galaxy cluster. With a large amateur telescope (size does matter) literally hundreds can be spotted within the boundaries of Virgo. Those with more modest equipment can still spot dozens of galaxies.
An easy way to determine if a zodiac constellation is currently visible at night is by the current astrological "sign". The sign is current when the sun is within its boundaries and therefore that constellation's stars are hidden by the sun. The sings to the left and right of the current sign would also be hidden in the daytime sky, the next two would be near the sunrise and sunset skies, etc. The exact opposite constellation to the current sign would be at zenith at local midnight.
PS to GreenWitch: I was only teasing and not trying to be mean.
PSS to GreenWitch: As for breaking the Prozac in half; I did some consulting to a major pharmaceutical company for several years so I can say this with some professional credibility: neither you nor any of your science advisors should ever change dosage or discontinue any meds without consulting your doctor, especially the major anti-psychotic drugs. :wink: