It's impossible to cancel services -- I'm moving and Xfinity doesn't service new area

Hello, I'm sure everyone has heard this a million times now due to Xfinity's reputation.

I moved recently to an area that Xfinity does not service and have been trying to cancel services at my old address. Of course, they make it impossible. If I click the "move address" options on their website and since they don't service my new address the page intentionally breaks. They can say it's not on purpose, but everyone reports this happening, it's clearly on purpose.

If I call them, I'm put on hold for hours and hours. The nearest store is an hour from me and I can't find the time to go. 

It's not like I'm dissatisfied with the service, I just don't live at my old address anymore. There's no one living there and I'm being forced to keep paying for a service no one is using or going to use. I'm going to sell my house! I don't need service anymore there.

How am I supposed to cancel services?? Why can't they just make this easy?