12 th House and Relationship

Venus the planet of relations:- 

The 12th house is the house of illusion, Secrets, ideals, Deception and self-Deception, dreams, drugs, chronic illness, institutions (hospital, jail) and intuition. 12th house is the house of shadow, secretes, loss, sorrow, escapism, bed pleasure and isolation.
                 

Planets in 12th house and ruler of 12th house shows, areas of life that is likely to lead to a loss. 12th house is considered a malefic house and this house produces problems in our lives and any secretes in relationship can leads to big problems. Of course, loss also can lead to great spiritual growth, so this house should be seen as a bigger picture of life.

Planets in the 12th house of any one of the partner is important clue about personality, as 12th house is near to first house especially if the planet more than 20 degree.

When the partner's planets are in the individual's twelfth house, and especially when they make conjunctions with natal planets already there, the existing twelfth-house planets and the house as a whole are "woken up. " The partner causes the individual to have to look at his or her hidden twelfth-house issues without any specific triggers. The individual may experience the relationship as intense and challenging.  In the context of a relationship, the main planets to look for is the planet Sun, Moon, Mars, Venus, and the rulers of the 7 th and the 5 th house.

When one of the partners has the Sun in the twelfth house, (Sun is the individual power) and it is likely that other people don't really see this person individuality, or the individual's own deliberate efforts to hide this and the other partner doesn't able to understand very well.

When one of the partners has the Moon in the twelfth house, it usually shows a problem in expressing feelings. This might be because of the fear of loss or sorrow, probably because it has been experienced before. It is not an uncommon problem for some people to avoid becoming deeply involved in a relationship because of the fear of loss. Moon can be a great help for the partners to understand the problem and find safe, conscious ways to deal with emotional problems.

When one of the partners has the Venus in the twelfth house. Venus is the natural signification  for relationships, but that does not make a good place to have Venus in 12th house, in a relationship. There can be too much secretiveness. It is not unusual for people who have extramarital affairs to have Venus in this position, and automatically make someone unfaithful.

This also May be the case for a partner who has the ruler of the fifth in the twelfth. The ruler of the seventh in this house also makes for secretiveness about the partner, about relationships, and even toward the partner, but not everyone with a twelfth-house Venus or fifth lord is likely to have an affair or secretive. Venus,  ketu conjunction gives secret relations.