What an excellent interpretation of that transiting aspect, Curious!
And yes, it has a lot to do with the interaction with others in all kinds of relationships, attachments to others vs. understanding the self, and attempting to break away while sometimes holding on at the same time. So relationships with people, which have always been difficult for this person to begin with, have been affected. And as an aside, the comforts of life in general (and income) may have been affecte dto come degree during the transit, as Venus is sometimes associated with that, and Uranus opposite Venus and Chiron is in the 6th house of work and service 9which is also health).
Now this Pluto transit could have begun to affect this person's Venus/Chiron conjunction as early as March of 2007 (perhaps earlier). Pluto again made close contact to the opposition in December of 2007 and into 2008, where it may have been particuarly intense. (We seen inconjuncts from transiting Saturn in Virgo to the Venus/Chiron in 2007 and 2008 as well.) And although retrograding Pluto may have backed far enough off of the aspect in August of 2008 to relieve the tension, it then turned direct again, so it never really left. By October of that year it really gained strength in the aspect, and was back in Capricorn by November. And we can see where this led in 2009 as Pluto more directly squared the Venus itself as it moved back and forth. It has never left that aspect, really.
Although Pluto has been approaching and retrograding all around this square since about March of 2007, notice that this person's Uranus at 26 Virgo is opposite her Chiron and Venus in the early degrees of Aries (an "out of sign" aspect). So Pluto may have touched off the opposition evern sooner, as it was in Sagittarius squaring this Virgo Uranus.
My feeling is that the past couple of years so so have been VERY hard on this person emotionally and psychologically, and perhaps even physically. This person could have hurt herself, or made herself literally sick, but the source was emotional and psychological pain. She may have isolated herself, or she may have had to go into some kind of hospital or program such as a rehabilitation program. Perhaps she required medication, etc.
Yes, it's very possible that relationships with people have been transformed, either through death or "break up" or other forms of separation. it's possible that some relationships went to dark or angry places, or there was jealousy and possessiveness, or that things were sexualized in a darker sense of the word. It's a difficult square, and with Uranus involved in an opposittion to an already sensitized and painful Venus and Chiron conjunction in the 12th, there may have been extreme and sudden departures that led to even suicidal impulses. This has been very, very hard on this person, yet because of the 12th house involvement, they may not have expressed the extent of their pain soon enough.
There may be some relief for this person in June and July of 2010, while Jupiter enters Aries and passes over her Chiron and Venus, hopefully in a healing way that promotes an enlightened level of consciousness to those locked up 12th house planets. 12th house planets CAN see the light in different ways. But then in July, as Jupiter hangs around those planets and retrogrades back over them, Pluto makes another pass through that square aspect which continues through August and September. Perhaps that retrograde and direct motion will not be felt as strongly as the previous ones if this person has been helped sufficiently, but we don't know. This pass seems to indicated a purging and release which combined with Jupiter, may be quite different, particularly in early August when Mars in Libra is opposite the Chiron and Venus in Aries. Let's hope this is truly a healing circumstance rather than anything else, as there is some danger to how this person may bring this about. They may want to exterminate the ego through exterminating the attachment to the other in their own heart. The best way to do this is to find closure by rising above it all.