Severe hip and lower back pain with nerve discomfort in a postmenopausal woman with Osteoporosis may be due to vertebral changes or nerve compression (like Sciatica). Cold exposure can sometimes worsen nerve sensitivity. You should avoid cold triggers, use warm compresses, ensure adequate calcium and vitamin D, and take pain relief like Paracetamol if needed. Since pain is severe and persistent, consult a doctor for evaluation (possibly repeat imaging) and proper treatment to prevent fractures and manage nerve pain.