Transparency When DistanceProblem

So I'm trying to make a sprite have a different alpha value when the player sprite is a certain distance from other people sprites. Right now I have no errors, but the code isn't doing what I want it to.

I have this code attached to each sprite that will affect the distance in order to decide the alpha of the overlay (a sprite that covers the entire screen).

using UnityEngine; using System.Collections;

public class transparentAnxiety : MonoBehaviour {

 public GameObject overlay;
 private Color alphaColor;
 public GameObject sprite;
 public GameObject player;
 public float distance;


 public void Start()
 {
     alphaColor = overlay.GetComponent<SpriteRenderer>().material.color;
     alphaColor.a = 0;
     overlay.GetComponent<SpriteRenderer> ().material.color = alphaColor;
 }
 public void Update()
 {
     distanceCheckSprite ();
 }

 public void distanceCheckSprite(){
     distance = Vector3.Distance(player.transform.position, sprite.transform.position);
     if (distance < 3){
         alphaColor = overlay.GetComponent<SpriteRenderer> ().material.color;
         alphaColor.a = .3f;
         overlay.GetComponent<SpriteRenderer> ().material.color = alphaColor;
     }
     if (distance < 2) {
         alphaColor = overlay.GetComponent<SpriteRenderer> ().material.color;
         alphaColor.a = .6f;
         overlay.GetComponent<SpriteRenderer> ().material.color = alphaColor;
     }
     if (distance < 1) {
         alphaColor = overlay.GetComponent<SpriteRenderer> ().material.color;
         alphaColor.a = 1;
         overlay.GetComponent<SpriteRenderer> ().material.color = alphaColor;    
     }
     if (distance > 3) {
         alphaColor = overlay.GetComponent<SpriteRenderer> ().material.color;
         alphaColor.a = 0;
         overlay.GetComponent<SpriteRenderer> ().material.color = alphaColor;
     }
 }

}

Any help would be awesome!