The 12th House is perhaps the most difficult one as far as rational explanation and understanding are concerned. At a high level, the Twelfth House embodies direct communication of men with God; at lower levels, essentially the same thing happens but we do not always understand and accept it, which leads to many a false interpretation.
Astrologers attribute many circumstances of human life to the 12th House: internal and external loneliness, hospitals, prisons, secrets and secret enemies, irrational fears, religiosity, mysticism, karma, previous incarnations, etc. What do all these things have in common?
At the level of subjective perception, the general mood of the 12th House is a feeling of mystery or a subtle (but very important and hidden) notion of what is happening to you. A person with a strong Twelfth House can spend a whole life searching for this notion, sometimes within him- or herself, sometimes in external activity, but constantly striving to surpass the current level of understanding and touch the sublime.
12th House Synastry
The interpretation of the 12th House synastry is predicated upon the strength and development of this House, as well as its position in your natal chart. For example, your reaction to your partner as a potential conductor of God’s will depend, to a large extent, on your religious and mystical attitudes as a whole. If they are sharply negative, then many of the effects of your partner’s planets in your Twelfth House will go unnoticed or cause an a priori hostile attitude.
If your Twelfth House is strong, then a significant portion of your life will be taken by acts and circumstances that you consider sacrificial, and it depends on you in many ways whether these sacrifices will be made by you, to you, or near you. The partner’s planets located in your 12th House emphasize the issue of sacrifice for you both. And while it is generally supposed to be you who makes a sacrifice, the partner will also be a sacrificial figure, at least to some extent.
However, perhaps the main point of the 12th House is to uncover a secret that the Absolute reveals to you as a result of long and difficult searches and selfless sacrifices. This mystery can be revealed through the synastric planets of the 12th House, but the revelation is still predicated upon your honest efforts. And, while it may seem that your partner revealed the secret to you, it is more correct to assume that the egregor entrusted your partner with this task when it considered your preparation complete.
The partner, however, may be inclined to intrigue you with their mysterious behavior without actually having anything that might interest you. The synastry planets of the 12th House will push her to such behavior, and you should be patient and remember that (1) you’ll find out everything essential in due time, and (2) that the information will come through several channels. And remember: information that is unverified or comes only through a single channel is either false or insignificant.