A few weeks time? She's out banging a few other guys to see if you're worth her time in bed...Maybe. Basically you should accept that she'll probably sleep with at least one guy here shortly if she hasn't already.
However, if you don't give her the space she'll run anyway. So pretty much damned if you do, damned if you don't. Take some time, address things in yourself that are causing you to be a freakish controlling asshole, then see how it all turns out.
Maybe you'll find someone much better, and appreciate her far more now that you've lost something you valued.
"Well, then," the Cat went on, "you see a dog growls when it's angry, and wags its tail when it's pleased. Now I growl when I'm pleased, and wag my tail when I'm angry. Therefore I'm mad."