You could be looking for someone who has the same personality as the person you used to love before, but who was not the ideal partner for you. This means that you will have a relationship with someone who will simply repeat the mistakes of your ex boyfriend or girlfriend.
For example, if you tend to like very handsome men or women, you will certainly have many deceptions because they are too vain and selfish. You have to look for someone who will respect you, instead of cheating on you like your ex.
You could also be looking for a partner who will feed your complexes and give you a feeling of superiority and safety. This means that you are looking for a doctor or a parent, and not for a man or woman with whom you will be an equal partner in the relationship. You are looking for an authority figure.
If you see in a dream a boyfriend or girlfriend you had a long time ago, this happens because the unconscious mind is reminding you about the unfortunate circumstances involving that previous relationship. Your dream is warning you that you are about to get involved with someone that looks like your previous mate and won't make you happy.
However, if you have separated recently, chances are that you are still in love with your old boyfriend or girlfriend. In this case, you keep dreaming about him or her because the unconscious mind is showing you that you have not yet overcome your feelings associated with the separation.
These dreams work like warnings; they don't let you fool yourself in believing that you got rid of the feelings you have for your old partner. They are telling you that you are still vulnerable to accepting a reconciliation.
If you had a bad relationship, you should stay far away from your old partner. You have to stop thinking about getting back together. Insisting on continuing a problematic relationship is a very silly mistake; you can only suffer if you stay with the wrong person.
There are cases in which the dreams about your ex boyfriend or girlfriend are trying to show you that there are many positive aspects in their personality that you should observe, because your ex could make you happy.
You will see dreams indicating that you must pay attention to the personality of your old partner in case you will unfairly despise him or her.
You may have dreams about your old partner, if you have left him or her because you felt attracted to someone else who will only make you suffer. In this case, the unconscious mind will be sending you dream messages that your ex is the right person for you and not the man or woman you feel attracted to. This is an attraction that will disappear once you understand who they really are.
Each case is different...
You should learn how to translate your dreams according to the scientific method of dream interpretation to find out which exactly is your case, and then you must follow the unconscious guidance with precision.
The unconscious mind will help you find happiness with the right person instead of repeating old mistakes, or instead of losing your perfect match because you are being superficial in your search for the right mate and your efforts are futile.