My sympathies. I had Bells, started June 2001. I was taking classes at the time and had physician clear me to dive, with precautions. The dive shop had no problems letting me dive. However, due to some of the issues aquaviper states - inability to close eye, inability to fully close mouth around reg, and high doses of steroids, I did not get in the water. Let's face it, I couldn't keep food in my mouth, let alone feel secure with a reg at depth. I was out of the water for 3 weeks.
The steroids worked pretty quickly and I also took antioxidants and vitamins (especially B complex). Fairly complete resolution within 3 months. I still have residual problems, one eye (the first site to hit) droops and tears up constantly, I get stress headaches if I am on computer too much. But most people can't tell.
The source of Bells is not really known, virus may be indicated, some claim episodes of Lyme disease can trigger (I have had Lyme), stress (I was going through a separation at the time), accident, dental work if the hit the nerve the wrong way. Who knows?
I am not a doctor and any information is given as a former Bells sufferer, based on my personal experience. You mention your trip, but not the remaining time until you leave. Talk to your Doc about how long they estimate resolution. Good luck and keep us posted as to your progress.