Hmm. Are you sure you're doing everything right? Looking around at everything closely. Becoming aware of all the colors, sounds, sights, etc around you? Then really questioning if it is a dream several times throughout the day? You haven't just made it into a habit you don't think about?

Like Lizh said, if you really don't feel like it is working you can try switching techniques for a while, or taking a small break from LDing. It's good you have been sticking with it for 2 months! Sometimes it takes longer for different people. Just remember to be confident and believe that you will really have a lucid dream tonight. Good luck