Why does my ex's new girlfriend keep calling me and sent me a text?

You're young, even with a child you can have your life success but without your child's father. You really should consider your ex as your child's father, no more, no less, he will only weigh you down. Any man who allow verbal abuse to someone whom he claim to love is not a real man, he is a loser, write him off, don't depend on him. Start your own life, continue your education, get your career going for the sake of your child.