I've got a Windows Phone 8 as well, and it doesn't support reading texts either.
As far as I know the text support isn't available in any Windows phones currently on the market, so I think you'll just have to wait and hope for an update to the phone (that's what I'm doing anyway)
My Nokia 920 works well with Sync, but it's actually the phone that does the work, as it also works with my wife's Qashqai and my Bluetooth headset. I can listen to, and reply to texts using speech only, even on my bike!
Go to Settings/Speech and set Read Incoming Texts Aloud to Bluetooth and Headsets. I also have the Use Speech when the phone is locked, and Enable Speech Recognition Service option ticked in the same menu.