object reference not set to the instance of an object line 29. i want to get script of playermovement and if isattacking equal true i want to kill enemy. c# unity5

using UnityEngine; using System.Collections;

public class Enemy : MonoBehaviour { public float playerDistance; public Rigidbody2D playerRB2D;

public PlayerMovement playerMovement { get { return GetComponent(); } }

 // Use this for initialization
 void Start() {

 }

 // Update is called once per frame
 void Update() {

     GetComponent<PlayerMovement>();


     playerDistance = Vector3.Distance(playerRB2D.transform.position, transform.position);

     if (playerMovement.isAttacking == true) //this line 29
     {

         if (playerMovement.isAttacking == true && playerDistance <= 1)
         {
             Debug.Log("Die");
             Destroy(gameObject);
             playerMovement.isAttacking = false;
         }

     }
 }

}

using UnityEngine; using System.Collections;

public class PlayerMovement : MonoBehaviour {

 private Rigidbody2D rbody;
 private Animator anim;
 public bool isAttacking = false;
 //public float enemyDistance;
 //public Rigidbody2D enemyRB2D;

  

 // Use this for initialization
 void Start () {
     rbody = GetComponent<Rigidbody2D>();
     anim = GetComponent<Animator>();
 }
 
 // Update is called once per frame
 void Update () {
     Vector2 movement_vector = new Vector2(Input.GetAxisRaw("Horizontal") , Input.GetAxisRaw("Vertical"));


     //if not zero must be moving
     if (movement_vector != Vector2.zero)
     {
         anim.SetBool("isWalking", true);
         anim.SetFloat("input_x", movement_vector.x);
         anim.SetFloat("input_y", movement_vector.y);
     }
     else //sees if in idel or not changes anim
     {
         anim.SetBool("isWalking", false);

     }
     //movment by 1
     rbody.MovePosition(rbody.position + movement_vector * Time.deltaTime);

     //sets attack to true if space hit
     if (Input.GetKeyDown(KeyCode.Space))
     {
         isAttacking = true;
         Debug.Log("Attack");
   
     }
     //Makes anim attack
     if (isAttacking == true)
     {
         anim.SetBool("isAttacking", true);

         isAttacking = false;

     }
     else
     {
         anim.SetBool("isAttacking", false);
     }

    




 }

 // checks if touch enemy and then if can attack then kill
 //void OnTriggerEnter2D(Collider2D other)
 //{
 //    {
 //        if (other.gameObject.tag == ("Enemy"))
 //        {
 //            enemyDistance = Vector3.Distance(enemyRB2D.transform.position, transform.position);
 //            Debug.Log("Touch");
 //            if (isAttacking == true && enemyDistance <= 1)
 //            {
 //                Debug.Log("Die");
 //                Destroy(other.gameObject);
 //                isAttacking = false;
 //            }

 //        }
 //    }
 //}

}//end