Why are Textures applied to multiple materials script.

My question is about an issue on texturing materials and placing said materials onto objects through script. currently I have two buttons one to place a texture onto the front face of a card and one to place a texture onto the back face.

When I do it the first time it works fine only applying the texture onto the one face. However any subsequent presses and the texture for both materials that are on the faces change.

NOTE each face is a separate game object.

Updated the Code here with Edit: I did end up getting it to texture the front and back of cards and materials separately however I ran into another problem where when I created a copy of my card object and then changed the texture on it again it would then change the texture on the materials attached to the other cards as well. I currently have it set up so that each card has two cube objects back ot back one called "front" and one called "Back" could it be because of the commoon name that it is doing this meaning I have to change the names of said parts of objects?

 // Scripts
         public Colomn1 colomn1Script;
         public Colomn2 colomn2Script;
         public Colomn3 colomn3Script;
         public Card aCard;
 
         //Objects
         public GameObject card;
         public GameObject holdingCard;
         public GameObject colomn1Object;
         public GameObject colomn2Object;
         public GameObject colomn3Object;
         public GameObject frontObject;
         public GameObject backObject;
         public Texture2D frontTexture;
         public Texture2D backTexture;

 frontTexture = new Texture2D (1, 1);
 backTexture = new Texture2D (1, 1);
 colomn1Object = GameObject.Find ("Colomn1");
 colomn2Object = GameObject.Find ("Colomn2");
 colomn3Object = GameObject.Find ("Colomn3");
 card = GameObject.Find ("Card");
 holdingCard = null;
 frontObject = GameObject.Find ("Front");
 backObject = GameObject.Find ("Back");
 
 void CreateMaterial (Texture2D texture, GameObject gameobject)
 {
     // Create a simple material asset
     var amaterial = new Material (Shader.Find ("Diffuse"));
     AssetDatabase.CreateAsset (amaterial, "Assets/Materials/" + cardName + ".mat");
     
     amaterial.mainTexture = texture;
     gameobject.renderer.material = amaterial;
     //gameobject.renderer.material.mainTexture = texture;    
     
     // Print the path of the created asset
     Debug.Log (AssetDatabase.GetAssetPath (amaterial));
 }

   

   
 if (GUILayout.Button ("Add Texture to front of Card")) 
 {
     side = "front";
     if (cardTypeToolbarInt == 0) 
     {            
         cardName = "Play_Play_" + seriesText + "_" + copy.ToString () + "_" + index.ToString () + "_" + side;
     }
     //    camera.SelectCamera (0);
     string file = EditorUtility.OpenFilePanel ("Hello", "", "png");
     if (file.Length != 0) 
     {
         WWW www = new WWW ("file:///" + file);
         www.LoadImageIntoTexture (frontTexture);
         CreateMaterial (frontTexture, frontObject);
     }
 }
 
 if (GUILayout.Button ("Add Texture to back of Card")) 
 {
     side = "back";
     if (cardTypeToolbarInt == 0) 
     {
         cardName = "Play_Play_" + seriesText + "_" + copy.ToString () + "_" + index.ToString () + "_" + side;
     }
     //    camera.SelectCamera (1); 
     string file = EditorUtility.OpenFilePanel ("Hello", "", "png");
     if (file.Length != 0) 
     {
         WWW www = new WWW ("file:///" + file);
         www.LoadImageIntoTexture (backTexture);
         CreateMaterial (backTexture, backObject);
     }
 }


 if (GUILayout.Button ("Save Card too Deck")) {
     
     
     
     
     
     index++;
     if (repeat == true) {
         copy++;
     } else {
         copy = 0;
     }
     if (int.TryParse (randomNumberText, out randomNumber) == true && randomNumberText != "") {
         aCard.RandomNumber = int.Parse (randomNumberText);
         //aCard.name = cardName;
         aCard.Colomn1Header = colomn1Text [0];
         aCard.Colomn2Header = colomn2Text [0];
         aCard.Colomn3Header = colomn3Text [0];
         
         for (int i = 1; i <= 10; ++i) {
             int.TryParse (colomn1Text [i], out aCard.Colomn1Values [i - 1]);
             aCard.Colomn2Values [i - 1] = colomn2Text [i];
             int.TryParse (colomn3Text [i], out aCard.Colomn3Values [i - 1]);
         }
         
         if (deckCount == oldDeckCount) {
             deckCount += 1;
             holdingCard = GameObject.Instantiate (card, new Vector3 (1.00f, 1.00f, deckCount * 0.05f), Quaternion.identity) as GameObject;
             if (side == "front") {
                 cardName = cardName.Remove (cardName.Length - 6);
             } else if (side == "back") {
                 cardName = cardName.Remove (cardName.Length - 5);
             }
             holdingCard.name = cardName;
             var prefab = PrefabUtility.CreateEmptyPrefab ("Assets/Prefabs" + holdingCard.name + ".prefab");
             PrefabUtility.ReplacePrefab (holdingCard, prefab);
             side = "front";
             oldDeckCount += 1;
             
         } 
     } else { 
         EditorUtility.DisplayDialog ("Enter numbers Only.", "Please enter a interger value as random number.", "OK");
         
     }
 }