Async readFile undefined

I believe I am having an Ansync issue in my code. I keep getting an "undefined" value. I have been trying to make adjustments based on this post but haven't had any success. Here is my current code where I can console.log() the value from within the fs.readFile

var fs = require('fs');
var csv = require("csv");
// *** START HERE ***
fs.readFile("contacts.csv","utf8", function(err, data){
    csv.parse(data, {columns:true}, function(err, parseData){
        console.log(parseData); // LOGS THE DATA
    })  
});

Ideally, I would like to have this 'parseData' array globally. I tried reading some of the suggestions from the link above and I get an "undefined" value. Here is my most recent attempt.

var fs = require('fs');
var csv = require("csv");
// *** START HERE ***
var friendsList; // define var in global space

function friendsListData(callback){
    fs.readFile("contacts.csv","utf8", function(err, data){
        csv.parse(data, {columns:true}, function(err, parseData){
            friendsList = parseData;
            callback();
        })  
    });
}

function returnFriendLists(){
    console.log(friendsList);
}
friendsListData(returnFriendLists);

This works, it console.log's the value. But this isn't what I want, I want the actual value so I can use it later, I would like it in a global variable. Is there any way of doing this? I tried changing my returnFriendLists function to:

function returnFriendLists(){
  return friendsList;
}

But still receive "undefined" when I console.log(friendsList) globally.