This is easy to cure, buy a big pump-can of lube, and dildos in various sizes. Play with them until your vagina start liking it. We used to call it "Like a Virgin" back in my younger days. Lube is your friend, use a lot of it and just gently work your ways up to it.
Also, Seth, try throwing on a condom and do some anal. :)
Best of luck to you two ;)
That's essentially what dilators are. As you can see in the photo above they range from very small until the get up to the size of an average penis.
It may be a simple cure, but it is definitely not easy. But you're right, lube is our friend.