It is a part of life, however some people are more severe than others. Maybe she is going through something you have no idea about. You don't just get over depression, or else you aren't depressed. You are just sad. Most people who are depressed usually do not even know. Some people choose to go on medication, while others try and overcome it on their own. I would estimate millions of people overcome depression, and there are some people sadly who cannot and choose to leave their life behind. If she is/was (didn't read the entire thread, sorry) depressed I hope she keeps fighting and is able to get the best help possible. "I'll keep my fingers crossed always for you."