I have been recently divorced and it can be such a hard thing for children
Divorce IS hard.  Annulments, declaring marriages null and void are so much better.  I, too, am divorced.
I have heard about annulments but don't know much about it. Isn't there a time period where you can file?
Yes, but I'm not sure how long.  Divorce isn't allowed in Vatican City or in the Phillipines.  Only annulments.
Only really? Now that is very interesting. Do you have any statistics on the number of divorces on average?
One measure of divorces is the crude divorce rate, which is the number of divorces per 1,000 people, and I'd guess 500/1000