Depression of the kind you describe, results whenever we suppress our true nature and our ability to express ourselves in alignment with that nature. You're all locked up. Consequently the first remedy I would prescribe is to join up with a team of men and go off and do something manly and energetic - like hiking or surfing. Get your physical energy moving in a natural environment. Doing this will help you to:
The next step is to start to look at your life afresh. Ask yourself what you are really meant to do with your life. Don't be concerned with how this new direction will come about - focus more on what if I could do this... or that... or the other. Write down your thoughts or draw images of them if you are so gifted, and place these musing on the kitchen cupboards, where you can look at them regularly and discuss them with visitors to your home. Make this a game of escaping from the world as it is, into the world as you would like it to be. See if you can sense energy behind these thoughts in the form of enthusiasm and a willingness to explore further.
The next step is to explore the most promising. To do this, open up a direction toward achieving some of these aspirations. Do you need training?... pick up the phone and ring a training organization. Do you need support?... ring a friend who is positive and supportive and ask him/her to help you. Do you need to learn more about the subject?... jump into the internet and surf the web, learn more about the subject and contact a few people. Get the idea.
Then keep going with this process until you life purpose comes clearly into view. As you focus on and do work that you love, your ability to express your talents in constructive ways will develop and your depression and lethargy will become a thing of the past.
Be aware of any negative "self-talk" that may be holding you back and cramping your positivity. As you move forward through these stages learn to be aware of how you are supporting yourself through your thoughts. Develop the habit of watching your own mind working - as if your mind belonged to someone else. In this way you become aware of your thoughts and can notice when your thoughts are turning negative. Noticing this tendency every time it happens is sufficient to greatly reduce the impact of negative thoughts and accelerate progress.