There are experts, such as psychologist Margaret Wehrenberg, who believe that anxiety and depression should be treated as chronic conditions.
If these are fairly entrenched as a part of your personality and the way you exist in the world, I happen to agree. However, the very good news is that you can learn coping skills to help you manage these aspects of yourself.
Realize that there are many parts of your being, and that simply because you endure anxiety or depression, it does not mean the rest of your life need be canceled out as a result. There is so much joy to be found in realizing that you have the control, and the ability to determine when these aspects will come to the fore, or recede, based on the skills–that you can learn–when you choose!