I know exactly what you're going through. I weighed in at 180 about a month ago then gained right back to 183, for no reason, now my period is about to start and I'm at 186, again. It's enough to drive you crazy.
I read an article about how to get off the plateau by getting off your diet for a week. I've been off for 4 days but I'm ready to go back on. I just can't handle that much fatty foods much longer. I'm starting back tomorrow. I will post on how it worked. The article I read said it will trick your body into thinking that you are no longer withholding calories and then you should start losing again. We'll see. I can tell you I've not gained any. A matter of fact, I lost one of the pounds I had gained.