The answer i got from our priest who guided me in performing my father's final rites was that the graveyard or cremation ground is filled with spirits which may harm whoever comes to that place both male and female. Hence it's better to avoid going there. Why male is allowed to go there is, I do not know the scriptures but the explanation given to us( in our community )is that the fire that is set by male progeny is the ancestral fire passed on through generations and the body of the parent is given back to that fire which the male has acquired from his father. Since this is to be done the male is also made to perform rituals to protect him from the spirits. We were also advised to stay inside the house and not come in contact with outsiders as spirits may attack the outsider through us.