From common sense, it seems pretty hard to accept the existence of magnetic monopoles, unless there also exists some "fundamental" monopole-particles. I think so because all the fundamental particles what we know until now are magnetic dipoles, e.g. electron, protons etc. (please correct me if I am wrong). Therefore, any physical object consisting of these fundamental magnetic dipoles, will either be a magnetic dipole or neutral. So, how can a magnetic monopole exist in reality if there is no "fundamental" particle that is a magnetic monopole?
(The field lines, electric or magnetic, are non-physical (this is just a concept that ease up the process of understanding). So, although it is acceptable from theoretical point of view to have a magnetic field line spreading from or converging into a magnetic monopole, I seriously doubt its physical existence.)
Would you mind shedding some light about it in simple terms?