Welcome to the desert of the real. There's a few of us here.
1st: Get tested for VD immediately.
2nd: Read the introductory manual (attached). Hit the gym, lawyer up, and try to take half her (your) shit. Then, start executing attached plan every weekend without fail. Execute it at the grocery store. In the checkout line at the clothing store. When you are at the bank, or just out and about.
Don't even bother to thank me. Just take this advice, and run with it. You'll be a changed man forever, and you'll also learn, in the process, what exactly happened to her.
Use the VD test in court if you get an anomalous result.