Is insomnia a symptom of depression or stress and how do I cure it?

It can be. The classic form of sleep disturbance with depression is early morning awakening (3-4 am), but some depressed people find it hard to fall asleep and then awaken multiple times during the night, finding it hard to fall asleep each time. Cure: psychotherapy is the best, medication can help.
It can be. . Address your depression ; your stress. Talk about feelings ; address problems. Don't avoid them. Aim for 7.5 - 8 hours of sleep/ night. Daily physical activity is optimal in a green space. Eat healthfully. Cut out junk carbs, caffeine ; alcohol (or moderate). Try qi gong, tai chi, acupuncture, acupressure, homeopathy, meditation, yoga, exercise program, deep breathing exercises or progressive >>.