You two might have an intense sexual connection, but it isn't rooted in a healthy feeling of compatibility and togetherness. In fact, it's probably just another forum in your relationship in which to act out an old power play that existed between you in a past life. You two were involved, long ago and in another lifetime, and it wasn't a happy experience for either of you.
You dominated this person, ruthlessly and relentlessly, and you cause them the same grief again if you're not conscious of how you treat them in this relationship. You might think that you're treating them just fine, when really you're dominating them emotionally on a subtle level. When they talk, you let them know it when you disapprove of something they're saying or doing -- and after a while, they feel afraid to speak their mind, to act in the ways that are most natural to them, because they know you don't like it. This may sound harsh, but keep in mind that you don't mean to treat this person in this way -- it is an old, unconscious dynamic rearing its ugly head again. It is within your control, if you're aware of it from the start. You should strive to let this person know that you want them to be themselves, and to speak their mind -- even when they say something you don't like or expect. Learn to love the differences between you, and the fact that you're both individuals.