Unwittingly, you will push your partner's karmic buttons regarding anger, rebellion and control. Even if they're normally quite a placid and accepting person, when you come into their life, you'll turn them on end emotionally. Though they won't realize it, they'll be recalling old feelings that date back to a past-life connection when you two faced off as dreaded foes.
That old feeling of enmity still hasn't dissipated, especially for your partner, and getting romantically involved in this life will mean always feeling that edge of irrational anger -- unless you can work together to resolve those old, outmoded feelings. For your part, you'll have to gently but firmly assert your independence, regardless of how aggressively your partner tries to keep you 'in line.' Behaving in a purposely unpredictable or untrustworthy way would be a mistake on your part, as it would only increase their sense of aggravation; but making it clear that you are and always will be your own person will be a very good lesson for them to learn -- albeit a difficult one. Both of you will have to use your words when working these issues out. Remember that acting on instinct will only perpetuate this tricky karma, rather than resolving it.