ok, i'm going to be more blunt now: i'm pretty certain she's an Sp-dom. at most, she might be Sx/Sp, but i highly doubt it, because when i first met her my Sx-dom aggression scared her.
Let's see, i'm going to highlight what i think is right from the enneagram website descriptions:
Self Preservation Instinct
People who have this as their dominant instinct are preoccupied with the safety, comfort, health, energy, and well-being of the physical body.(...) Self-Pres types tend to be more grounded, practical, serious, and introverted than the other two instinctual types. They might have active social lives and a satisfying intimate relationship, but if they feel that their self-preservation needs are not being met, still tend not to be happy or at ease. In their primary relationships, these people are "nesters"—they seek domestic tranquility and security with a stable, reliable partner.
Sexual (aka "Attraction") Instinct
The key element in Sexual types is an intense drive for stimulation and a constant awareness of the "chemistry" between themselves and others. Sexual types are immediately aware of the attraction, or lack thereof, between themselves and other people. The sexual type is constantly moving toward that sense of intense stimulation and juicy energy in their relationships and in their activities. They are the most "energized" of the three instinctual types, and tend to be more aggressive, competitive, charged, and emotionally intense than the Self-Pres or Social types. Sexual types need to have intense energetic charge in their primary relationships or else they remain unsatisfied. They enjoy being intensely involved—even merged—with others, and can become disenchanted with partners who are unable to meet their need for intense energetic union. Losing yourself in a "fusion" of being is the ideal here, and Sexual types are always looking for this state with others and with stimulating objects in their world.
Social (aka "Adaptive") Instinct
Social types adapt themselves to serve the needs of the social situation they find themselves in. Thus, Social types are highly aware of other people, whether they are in intimate situations or in groups. They are also aware of how their actions and attitudes are affecting those around them. Moreover, Sexual types seek intimacy, Social types seek personal connection: they want to stay in long-term contact with people and to be involved in their world. Social types are the most concerned with doing things that will have some impact on their community, or even broader domains. They tend to be warmer, more open, engaging, and socially responsible than the other two types. In their primary relationships, they seek partners with whom they can share social activities, wanting their intimates to get involved in projects and events with them. Paradoxically, they actually tend to avoid long periods of exclusive intimacy and quiet solitude, seeing both as potentially limiting. Social types lose their sense of identity and meaning when they are not involved with others in activities that transcend their individual interests.