Control and vulnerability will become issues between you the longer you stay together, and they may first make themselves known in your sexual connection. You may try to push your partner to lose or relinquish control in a sexual sense -- to make themselves vulnerable and expose their animalistic, needy side to you in a way that they won't be terribly comfortable with. For you, this kind of experience will be intensely transformative and compelling, but for them, it could simply be a tense, awkward experience, which will be a cue to you that they're still dealing with past-life issues of strength, vulnerability and insecurity.
They need to feel as if they have a certain measure of control over the world around them; their security needs are such that behaving according to the 'rules' seems essential. But you want to push past all that -- to plunge deeply into the memories and triggers that make you feel vulnerable or scared, and grow strong through pushing your own buttons again and again until they just don't bother you anymore. But be forewarned that this kind of approach may have a negative effect on your partner. A much better way to help them through their own insecurities would be to communicate with them about their feelings, gently and compassionately. Trying to understand them may even reveal something unexpected about your own emotional makeup.