My ex is doing everything he can to try an make me look bad he accused me of child abuse he calls the police to drop her this is harassment what can I

One of the things you can do is bring this to the Court's attention before he does. If he is filing police reports you can assume that he intends to use those reports in your custody dispute. Turn that around on him. Bring the reports to the court's attention especially if they are numerous and frivilous. Courts are familiar with this kind of gamesmanship.