How can I focus more on myself?

My whole life I have felt as though I need to help other people with their problems, yet I'm spiraling down a path of depression. I don't show it because I feel it will upset others, which will intern upset other people beyond that. Whenever I focus upon myself I become depressed and go into a self destructive behavior. My friends see me as their best friends and yet I'm in a state of well..nothing. I can't tell my psychiatrist because of this and I feel like I'm letting down the people around me If i even slip up this behavior. Has anybody every been down this lonely road? It's not depression, it's a path of..well normal to me. I feel as though this life as I know it is all an act to get to a greater point in my life that I know will never come.