If the cross through the ring is on your status page with her (where it shows her likes and dislikes, how much she loves you, how funny she finds you, and how attractive she finds you), then you only need to worry if the bar slides toward that icon. If she dislikes you enough to reach the icon then she will divorce you.
You may need to try a bit of seducing and chat-up lines to try and get her knocked up, and remember not to use a condom.
I got my first Fable 2 condom from a dig patch my dog found - happy days
Remember that if you're not careful about the sex, something like this may happen (happened to a friend of mine):
i had no protection so i now have a fetching combo of teh aids, syphallis, ghonnerhea, and crabs lol