I cannot tell you the meaning of dreams.
But i think a dream happens when there's an unresolved issue within
us.
There's a conflict in you, a part of you wonders what it is like to
be with him, and it manifested in your dream.
At this stage you should be considering your current relationship.
Whether you should still continue to be with him. I don't think its
fair if you no longer like your current boyfriend, but continue to
be with him.
Maybe you should give it some though, your current relationship
that is, more than the other guy for the moment.