When we analyze Charts it’s important to remember that not all people will use the Astrological symbols in only one way. the 12 house can be tricky because the archetype contains Everything within and beyond our understanding, including for example the collective unconscious memories, Akashik records, and basically all that we know and don’t know. why things we don’t know? because our soul chose not to remember it’s previous experiences in order to learn what needs to be learned in it’s current life, so we can continue our evolution.
It is said that when we leave our physical body (one of many bodies we have) we return to the place where our soul remembers again all past experiences and know all future ones.

So when we are in the 12H our experience is beyond time and space, and it can be difficult because we do live in a reality of time and space. the person with planets there can feel that life on planet earth are difficult to them, and they will look for ways to escape from the everyday boring reality (6 house) and find ways to elevate and sometimes to disconnect completely. they can think or feel that this is the way for them to handle life. but because their soul chose to go down to earth and have a body, 24 hrs a day and all Saturnian stuff that ruin the fun, instead of adjusting and adapting to this reality they will try to find the emergency exit. be it through spiritual quest, drugs or just sitting all day in front of the T.V unemployed and waiting for a miracle to happen. (of course this is not the only theme in the 12H).
another issue can be having no boundaries! they can get the impression that life will support everything they do, or they are not aware of this option…They can be very clueless and naive.

A few things that can be helpful for them are: to learn how to ground themselves, learn to have a routine, eat food that can nourish them and support their journey on planet earth, do a lot of body work and in general activate the lower chakras and heart center.   Also Very  important for them is to learn how to work with life as it is.

By having a stronger Aura / immune system they can function better and not be afraid or overwhelmed by things that come to them,  beyond their control, but to learn and see the opportunities and reword of taking an active part in creating their reality. learning to put healthy boundaries will also support them.

A good example to illustrate all this is Sara Ferguson, who was part of the Royal British family and have Mars, Mercury and Neptune in her 12H. she found herself needing to adjust from living with many servants and not doing any simple everyday things like cooking, or even making her own decisions about things, to moving after the divorce into a much more simple life, where she have to take care of things she didn’t do when she was married to Prince Andrew and living in the palace.
Another thing she was known for is her luck of boundaries, and I would also say luck the understanding of her public role. she was photographed topless and hanging with other Men etc. many scandals and her 12H was “helping” everything to be exposed to the public.
you can read more about her, and she have a very interesting chart to explore. also check her latest interview with Opera Winfrey http://www.oprah.com/oprahshow/Finding-Sarah-Ferguson where she tells Opera about all this.

More excellent information on the 12 house/Pisces/Neptune Archetype you can find in this book by Maurice Fernandez >>