Okay, there's no good way to sugarcoat this, so to put it bluntly: Take special care to be completely honest and straightforward with your lover, because you stand a significant chance of utterly misleading them through the course of this relationship. It might be due to intentional deceit, or to accidentally sending out mixed signals; but either way, they aren't able to see you clearly because they're wearing rose-colored glasses that obscure the truth. Things could turn out really different from what they expect when, after a while, they start to realize that you really aren't the person they thought you were.
But it isn't all your fault -- it is partially theirs, for not taking the time and making the effort to read your signals, pick up on your cues and figure out who you really are as a person. Of course, that's not really their 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, you misled your lover as to your 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.