I'm just about at your starting weight now, and I have just about as much to lose. I feel your pain...I was in a plateau for a while. I don't know what broke me out of it, but I did stop using milk for my evening vitamins (eating/drinking before bed), increased my water and my exercise, and became more dedicated to trying to measure my food.
Perhaps, as Barb wisely suggested, you can post your daily plan? There might be something stopping things up. However, it might just be a plateau you have to work through. Did you read RNMom's post? It's really inspiring for those of us suffering from plateaus.