Gwyneth Paltrow has experienced “waves of grief and sadness” since her children left home. The 52-year-old actress has daughter Apple, 20, and son Moses, 18, with her ex-husband Chris Martin, and Gwyneth has revealed that she’s struggled to adjust to her children leaving home to attend college. During a Q and A with her fans on Instagram, Gwyneth was asked: “How’s life as a free bird?” In response, the Oscar-winning star replied: “Thank you for asking. It’s very different. I have waves of grief and sadness.” On the other hand, Gwyneth acknowledged that there are some positives to her kids leav…