Because of today's high divorce rates, chances are your child will have many peers with only one parent in the home. You need to talk as positively about the other parent as you can without being dishonest. Even if you don't like him, he is someone special to your child. Encourage other male role models in your child's life. How your child perceives caring adults of either sex will affect how he or she will relate to others as an adult.
State laws vary about grandparents' custody and visitation rights.
By law, birth parents are the only ones who have rights and responsibilities toward the child. Grandparents, however, are important people in your child's life and history. They can also be very helpful. Look on their help, however, as a temporary solution as it is important for you to be independent eventually. If you do live with your parents, they have a right to insist on a few rules.