Okay, there's no good way to sugarcoat this, so to put it bluntly: Take special care to keep your eyes wide open, because you stand a significant chance of being utterly misled through the course of this relationship. It might be due to intentional deceit, or to accidentally sending out mixed signals; but either way, you aren't able to see your lover clearly because you're wearing rose-colored glasses that obscure the truth. Things could turn out really different from what you expect when, after a while, you start to realize that your partner really isn't the person you thought they were.
It isn't their fault -- it's yours, for not taking the time and making the effort to read their signals, pick up on their cues and figure out who they really are as a person. Of course, that's not really your fault, either. You're both operating under the sway of some pretty powerful influences -- for example, the fact that you've been involved before, in a past life. Then, as now, your lover misled you as to their intentions in the relationship. In that past life, the deceit was probably intentional; in this life, it isn't necessarily so, but the end results could be the same. So don't make the same mistake this time. Be really clear and realistic with each other, and yourselves, about what you're looking for, and what you have to offer.