I'm having trouble driving at night - halos appear around bright lights (headlights, stop lights, etc). any idea what might be causing this? tell me

Many possibilities: Anything that defocuses the incoming light to your eyes can cause halos. This could be something easy like nearsightedness or astigmatism which is remedied with glasses or contact lenses. It could be a warpage of your cornea, called keratoconus. It could be a cloudiness in the lens of your eye(s), called cataract. There are many other possibilities. You should see and eyecare professional.