Messages for Mac won't add my phone number
I've been using Messages on Mountain Lion for months with no problems. I added my phone number to the Messages app in account settings as soon as it was available and the app was functioning perfectly until about when I updated to iOS 7. Now my phone number is no longer included in the "You can be reached for messages at:" section in the account settings in Messages. When I select "add email" and type my phone number it just disappears when I hit return. Even if I don't hit return and just check the box next to it, eventually it just goes away. I have tried adding it every way I can imagine (adding +1, adding "()", etc.), and still nothing. I have also tried signing out of Messages on my Mac and iMessage on my iPhone, then signing back in, and still nothing. I'm at a complete loss here. Any thoughts would be appreciated.
Thanks!
MacBook Pro (Retina, Mid 2012), OS X Mountain Lion (10.8.5)