Let's take a look at your goals! I don't think there should be much difference in the way that men and women train. I think that goals should determine whether or not you should lift heavy. Generally speaking, if you're trying to get stronger and/or gain muscle, heavy weights are necessary. If you're leaning down and want to maintain muscle, it's important to push yourself with heavy weights. This will help you keep more muscle as you lose fat. Lighter weights can be great for reducing muscle mass, for a cardio workout, or to break through a plateau. It's not easy to gain muscle, and it's almost impossible to "get bulky" just by lifting heavy weights. So, if you want muscle, throw more plates on the bar!
Erin Stern, 2x Ms. Figure Olympia