I don't think there is one meaning of life. If you value the fact that your life must have a meaning - and it seems to me that you do - then give it one! It is up to you. Were you born to do a good job? Or to be a good father? Or to save animals? Or to explain the world to others? Or to write beautiful poems? Or invent things? Or helping people? I'm sure it's not depression that's meant for you... ;-))