Here is what I did;
First of all you need to sign up for a 'dropbox' account which is free, this allows you to host your file and create a link to it.
Once you have your dropbox account you can copy your .unity3d file into your dropbox public folder. Once it has copied you need to right click on the file, select dropbox -> copy public link. (It may be a good idea to past this into Notepad or something for now.)
Back in wix you need to add an HTML widget to your website.
Next you need to open the .html file created by Unity, but you will need to open it in Notepad so that you can copy the code and paste it into the html widget in wix.
Your next step is to look through the code for a reference to your .Unity3d should look something like this;
unityObject.embedUnity("unityPlayer", "WebPlayer.unity3d", 620, 349);
You should then paste you link that you copied from dropbox over the WebPlayer.unity3d, make sure that the link stays within the quotes ""
After that you should be able to publish your site and then play your Unity Game!
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