Weight training makes you bulky and masculine:
Testosterone is one of the main hormones responsible for muscle growth and women do not and can not produce as much testosterone as males.

Weight training makes you stiff and musclebound:
Performing exercise correctly and through the full range of movement will increase flexibility and increase stretching capabilities.

If you stop weight training your muscle will turn to fat:
Muscle and fat are two completely different types of tissues and one cannot turn into the other. Once you stop weight training your muscle mass decreases and your metabolism will slow down, increasing body fat.

As long as you exercise you can eat what you want:
If we are consistently eating more calories than what we burn in a day our bodies will accumulate these extra calories which will be stored as fat regardless of how much exercise we are doing.

Women only need to do cardio and if they decide to lift weights, they should be very light:
Muscle helps to burn extra calories. On average an extra 1 kg of muscle will burn an extra 60 calories a day. Only lifting light weights will not do anything for you as muscle responds to resistance, and if there is no resistance there is no reason for the body to change.