Seeing a stranger in the dream which says that he is your boyfriend means that you will become involved into a new romantic relationship. This dream can also sadly signify an end to an already existing relationship.
Seeing a friend in your dream that claims to be your boyfriend has a more benign meaning and it often signifies that you will become more close with the person in question. Things however will not progress to a romantic relationship.
If you see your boyfriend in the dream it can mean several different things depending on how he behaves in the dream towards you.
If your boyfriend is quite angry and aggressive towards you in the dream it means that you need to be careful of similar happenings in real life also.
If he is gentle and caring it means that your relationship with him will deepen on real life.
If he is uninterested or indifferent in the dream, it means that your relationship with him will temporarily cool off.
If you see that your boyfriend appears to be very old in the dream it means that you might concerned about the direction in which the relationship with him seems to be going in real life.
Seeing that you boyfriend appears to be younger in the dream than he is in real life means that you have a strong desire to further the relationship with him in real life.
To see your boyfriend being dead in the dream can mean that you have desire to end the relationship with him in real life. This interpretation is especially true if you have this dream several times.