Note 2: This conjunction also involves my Lilith, which helps a bit.
Neptune conjunct the Descendant is a loaded position, offering profound gifts along side of tragic difficulty. The 7th house is one of the most likely houses from which to project planetary energies and Neptune, a transpersonal planet, is not easily welcomed into one's personal repertoire. The result is that Neptune on the descendant is most often not expressed personally but, at least initially, through projection onto another. The most likely "other" is the romantic partner, as the 7th house rules relationships. The 'worse' definitely includes the aforementioned projection and also a host of lofty, nearly impossible to meet romantic expectations.
Neptune/Descendant see herself as the heroine of her life, which she regards as a movie or fairy tale, defining herself through dramatic events. It is very hard for her to see herself clearly or perceive what it is she truly means to others. Particularly in youth, the ordinary roles of child, student, mate, etc. are dull to the Neptune/Descendant native. She will seek to spice them up with other considerations and, as a result, makes her life (and the lives of her friends, family and lovers) chaotic. She's attracted exclusively to those who inspire her romantic fantasies and is rarely practical about her relationships, preferring the excitement of fantasy to more pragmatic concerns. Her romantic cravings often involve her in peculiar emotional and/or sexual situations from which she may find it very hard to extricate herself.
On the positive side, Neptune conjunct Descendant is a highly artistic placement, especially positive if she is paired with an equally as creative partner, and particularly if they can share this without letting competitiveness spoil it. If the Neptune/Descendant individual's expectation of perfect beauty is met this way, through shared aesthetics and creation, it may undermine many of the more negative implications of this placement.
Neptune conjunct Descendant is also an excellent combination for counseling potential. They are capable of being so intimately attuned to others on a deeply emotional level that they may seem slightly psychic. There is an inherent talent for psychological studies and for drawing innermost thoughts and feelings from others. It is often quite natural for a person with this placement to exist completely inside of emotional intimacy, regarding it as their default way of being. In many cases, Neptune/Descendant expresses itself as an unnaturally strong valuation of probing and affectionate relationships, and the individual will feel compelled to create such relationships often in varying forms. Any partner will therefore need to acknowledge that this relationship forming is a vitally important part of the Neptune/Descendant individual's life, and internalize that this compulsion toward emotional intimacy with others is not a threat to the relationship. If this level of understanding is achieved along side of a shared creativity, it's quite possible the relationship will be truly idyllic in the way Neptune/Descendant dreams.
Being so prone to projection, however, the negative possibilities for Neptune/Descendant are many. Most obvious is the expectation that she must find a perfect mate; a fairytale prince who will rescue her from her own fog so that she may live happily ever after. Neptune loves a good rescue-- almost as much as she loves a good fantasy. If the aspected individual is fortunate, Neptune/Descendant can show itself as simply a very romantic undertone to the personality, with a deep and abiding trust in the power of love. However, there is a danger that it may develop into an expectation that the mate must fulfill all of the individual's deepest needs, provide unconditional love and support under all circumstances, and also be charming and lovely at the same time. This blind expectation that their partner be the embodiment of all that is beautiful and delightful in the world is damaging to all involved.
The strange truth of heavily Neptunian partners is that they are often amazingly noble and forgiving where major incidents (which typically break up other partnerships & marriages) are concerned, yet are unable to tolerate day-to-day differences and disappointments with any degree of grace. Some Neptune/Descendant partners, consumed by their desire to have a perfect union, will manage to maintain the illusion of the perfect partner in the face of an astounding amount of evidence to the contrary. They will overlook ignorant behavior, make excuses for immaturity, protect a weak mate, and generally do whatever is necessary to protect their fantasy. This is only exacerbated by the Neptunian gift of always seeing the best in others. The Neptune/Descendant individual who is protecting such an illusion will not give it up until she is ready to do so on her own, responding defensively to any suggestion from others that her partner may not be who she insists s/he is. Usually the mate's behavior must clash violently with another, more highly cherished value before the Neptune/Descendant individual even begins to see a problem.
It's important to mention that the Neptune/Descendant person, in facing the crumbling of her illusion, suffers a pain that is so deeply psychological it can be crippling. It is so painful, in fact, that it can only be survived if the native is able to accept fully that she built the illusion herself, in her own mind, and that her partner was never who she believed him or her to be. Otherwise she is likely to feel so deeply betrayed that her interaction with the world around her changes so gravely that she may dissociate from it entirely. If the illusion can be seen as a personally constructed lie to the self, the Neptune/Descendant individual can then grieve for the lost dream, rage at the unfairness of it all, and eventually let go of it. Depending on the level of expectation invested in the relationship to being with, however, this process can take years.
One constructive choice for the Neptune/Descendant individual who simply cannot give up on this need for a perfect partner/perfect devotion/perfect union etc, is devotion to the ultimate partner: God. This can be achieved through the ministry, priesthood/sisterhood, or through missionary service. It is a choice which needs to be carefully considered, however, for it is all too easy for Neptune/Descendant natives to be overwhelmingly drawn to such a life without consideration of it's profound sacrifices. Some find that an unimaginable weight is lifted from their shoulders by devotion to a life of service as they find they are truly fulfilled through it- often for the first time in their lives. Others are so overcome by their connection to otherworldly perfection that they are even less able to accept human fallability.
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If the Neptune conjunct Descendant native has a strongly cardinal or fire element dominated chart (this is true of me in general, but also my Neptune/Descendant conjunction is in Sagittarius), she will typically adopt the savior role and find herself involved with tragic figures. This is a semiconscious procedure; few people deliberately saddle themselves with such a frustrating burden. The native falls in love with someone she truly feels she can help, someone who just needs a little propping up here and there in order to be ideal. Only when the illusion begins to crack does she see that her partners often do not wish to be saved, and are in the state they're in because of their refusal to help themselves. The native inevitably becomes the target of her lover's anger and frustration. They expect loving gratitude but generally end up with their mate's misplaced fury instead, as they lash out in fear at the Neptune/Descendant native who is "forcing" them to change. As a direct result of her choice of partner, the aspected individual will be continually punished, verbally attacked and emotionally blackmailed, when all she offered was loving help. If her misguided fantasy is not realized for what it is, under the burden of relationships with such victims the potential savior eventually becomes a martyr-- loving and supporting thanklessly until she is run into the ground and destroyed.
In order to make the most of this complex placement, Neptune/Descendant will need to first become fully conscious of her propensity toward illusion regarding her romantic partnerships. She will need to force herself to be constantly alert for the appearance of savior/victim games in her close relationships, games which can lead to abuse and an unimaginable kind of hell. She will need to take responsibility for her own spiritual and creative needs, and take steps to express them for herself (rather than using her partners to create the experience for her). This placement offers tremendous gifts; a rare talent for intimacy, a nearly psychic perception, and deep insight into the emotional realm. This insight, however, includes the ability to fully fathom the pain of others, a gift she must keep watch carefully so that it does not overwhelm her.