Yes I know exactly how you feel. I am experiencing a pretty severe bout of depression as a result of my divorce; however I have actually suffered from anxiety/depression since college. Difference is, before it was manageable and I felt mostly normal. Now I definitely do not feel normal, I suffer daily, and I have a 16 year old son. It is a lot of pressure to put on a happy face, so to speak, and it takes a lot of energy to behave in a relaxed manor so that my issues don't rub off on him. In fact, I worry incessantly that he will end up with the same problems as me. It is a never-ending, vicious cycle.
I am working hard to make myself better. I am seeing a therapist, and I am in the process of finding the right med(s) so that I can pull myself out of this. Even in my darkest moments I feel a sense of hope. Doesn't make a lot of sense, but it's true. There is always hope, and there is help. I know I deserve a better life than this, and I know I will get there. You will too. It's okay to be vulnerable. You might have to step out of you comfort zone a bit to fight for what you need, but it is worth it.