Yes it is possible to get chronic depression from stress. Many people go through depression after a stressful event in their lives. Let me give you an example, after the death of my dog (a very stressful event in my life) I got into depression. There could be a lot of reasons like losing a loved one, a break up in your relationship, losing a job and so on. The key factor is how you are going to get out of it. Join a yoga or meditation session. Meet people and don't keep to yourself. May be you can spill out your frustration and pent up emotions to a friend.