I have observed that my sex drive has diminished after having a child. My son is 6 months old now, and oftentimes I decline my hubby's invitation for a 'quality time'. Is it normal to feel this way? How do you bring back the drive?

It's normal, don't beat yourself over it. The first 6 months of being a new mommy is hectic, busy and exhausting. I imagine it's the same for your husband and I'm sure he understands as well. Maybe you can get someone you trust (your parents or in laws) to watch your baby for a night while you and your husband have date night, be alone and to get intimate? :)