Uranus is the planet of freedom, disruption, eccentricity, unpredictability, and change. Venus rules romance, finances, materials possessions, and partnership.
As you may know, the composite indicates the fate of a relationship. You could have wonderful synastry, but maintaining a connection can be difficult in the face of a challenging composite chart.
Venus in aspect with Uranus indicates an off-beat, unpredictable, yet exciting relationship. Venus and Uranus usually bring together two people you would not think would ever be with one another. Others may see this couple as odd, non-traditional, and surprising. There could be a major difference in race, age, social status, location, or personality. Think about a stock broker suddenly falling in love with a hippie. You’ll find many long-distance relationships with this aspect, as well.
The relationship usually starts very suddenly. The feeling between the couple is electric; it is love at first sight. The sexual relationship often develops quite quickly, as well.
While things may start out well, there may be some difficulties in this relationship, especially if the aspect is a square or opposition. In these cases, it may be difficult to maintain the consistency of the relationship over time. This aspect can be quite frustrating for those who seek stability and calm in their relationships, as the relationship can, despite the couple’s best efforts, be the victim of sudden changes and unpredictability. The relationship may be quite odd. There may be long periods of absence/distance between the couple.
Couples with the square or opposition between Uranus and Venus in the composite tend to experience the worst parts of the relationship I just described. The conjunction can go either way. The trine and sextile are more subtle and pleasing, with just enough electricity to keep things interesting.
This is not to say that a relationship with Venus/Uranus aspect cannot last. My sister and her Husband have a tight Venus/Uranus conjunction in their composite, and they are in a lasting, committed relationship. They both allow one another a ton of room to breathe. My sister is an avid traveler, and she often takes off for a few weeks while her husband stays back to work. Their Uranus/Venus conjunction is also conjunct the Sun and Mercury of their composite, and the sextile to Saturn calms things down a bit for them.