Blue Rose is 100% dead-on. The well being of your child should come first, and foremost. Being with someone like this person only teaches your child that such behavior is not only acceptable, but appropriate.
The only way to excise NDP from your life is through "no contact." If you move in the same circles, then the circle of friends needs to be weeded out. Circling the wagons is a good analogy - but, only those people that have earned your trust need to be your friends, right now. Even then, this is going to have to be something that you do, on your own. You may even decide that hanging out with friends might need to be put aside for the best interests of your child - a very wise choice, in the long run.
Whatever you choose to do, you must do on your own. Nobody can do it for you and the control over your own life needs to be taken back into your own hands. Your child is watching you - every action and every REaction to Life's issues is training for your child as to what type of adult they will be. By remaining in a bad situation, they are learning that they must either become a victim, or an abuser, themselves. This may come across as harsh, but this choice is not only about you - it's about your child's best interests, as well. Both of my sons were raised in a NPD/sociopathic environment, and the long-term consequences of my choice to remain with a monster for that long have been dire. The eldest is a diagnosed sociopath, and the youngest is now the perfect victim. They are both adults, and the wake of damage that has been left is incalculable - from teachers, to taxpayers, to friends, to family.
Fairy Tales have taught women that they only need Prince Charming to be fulfilled. Well, it's rubbish. What we need is to develop into strong, wise, and self-assured human beings, and then we can choose a partner that's worthwhile! Women, in particular, need to realize that they do not require a man to be complete. You don't need this man. Your child doesn't deserve to experience this type of environment. But, only you can take the steps to end this mess and develop yourself into a strong, wise human being. www.lovefraud.com
Sincere best wishes to you.