Dismemberment of the body, or indeed any dream where some type of fragmentation takes place, is largely to do with being rendered powerless. It is the death, or rather dissolution, of the Self before reintegration and rebirth take place. Psychologically we need to take our old feelings and ideas apart to make sense of what is going on. This process has to take place before we can rebuild our lives. A situation may be tearing us apart and drastic action may be necessary before we can recover our equilibrium. You may also like to consult the entries for Amputation and Limbs in the Body section.
The fear of a family breaking up, or a romantic attachment being severed, is sometimes warned of by the dream of dismemberment, which means a breaking up. If you sometimes feel your live is coming apart at the seams, then this too will occasion a dismemberment dream. As in olden mythology, when man fell apart, the Gods would put him back together again, this then is a dream of warning you to change your ways, or take charge of a situation, before it reaches the dismemberment stage.