Hi Karen, my sympathies on your situation. Tony is correct in that this is definately a matter for the Police.
With that said however, you need to give careful consideration to what lies ahead. I don't mean to discourage you, however while you beleive that you are strong enough to deal with this now, that may not turn out to be the case. If he is charged and pleads not guilty (which sounds likely to me), then with a case like this, it is highly unlikely that he will ever be convicted unless you testify in a criminal court - and that is going to be very hard on you.
I therefore have some recommendations that I hope will help you out:
1. Speak to a lawyer and/or a counselor to learn as much as you can about the legal and court processes and what will/may be expected of you. Any counselling service that specializes in domestic violence or particularly sexual abuse, should be able to provide a ton of information for you.
2. Consider all outcomes and whether or not you think you can deal with each and every outcome. Reporting to the Police is one thing - a conviction is something else entirely. You need to know going in that you'll be able to cope with an aquittal if that's how it turns out.
3. This is the most important one - before proceeding, make sure that you have a strong support base around you (family and close friends). You will definately need all the support you can muster when the time comes.
Don't rush into this decision - it's a big one. Consider everything carefully and if you decide that you're up to it and you know that you'll have the support you need, then you have all my best wishes when I say "go ahead and nail his a**e to wall."