Hacking a cryptocurancy wallet can only be done if the private key is compromised. or Phishing. Maybe you clicked something on the web or in your email. Or the MEW phishing link. Or you download some malware on your computer. Perform a full scan on your PC and remove trojans / malware that steal your password. so the best thing to do is to ensure the security of your private key and think before you click on the web.