I used to have depression from early to mid adulthood that I could not shake off. Many times, it felt like it would never go away, almost like it was an integral part of me. When I was deep in my hole, I thought thoughts like "don't kid yourself, you're always depressed, this is how it is", and I certainly did not have any reason hoping I would some day suddenly not be depressed. But while it was not sudden at all, I am happy to say that I am now, by all means of assessment, not a person suffering of depression anymore.
I think in my case I was "lucky" that I did not want to take medication against it, any at all, and that my causes of depression did not require it. With a very big warning: It was lucky for my situation, and my apparent causes of depression. I do not want to assert that medication cannot help. My reasons for not taking medication were partly misguided, partly right (again, for my specific case). For example, I had the fear that medication would change my "personality" beyond removing depression, and I did not want to change my personality, because I liked the "good" part of my life, in the intervals where I was not suffering from depression too much (I say "too much" because I'm not sure I was ever really happy during that time). I don't think that's how the medication works, though.
So that left talk therapy, a lot of it. Years of it, sometimes interesting, often difficult. And through all of that, I discovered that I had reasons to be depressed, but I was very far away from seeing and understanding those reasons just on my own. They manifested as "generic" depression instead. Getting to those reasons and talking about them straight cured me. Part of it might have just been understanding my emotions at all. I am probably very lucky in that regard, going from "almost always depressed, sometimes too much to properly function" to "basically cured" by finding out what actually bothered me.
Not everything is rosy now, life does not work that way. Sometimes life situations make me sad, overwhelmed, even desperate, and may still send me into a depressive hole for some time. But when that happens nowadays, I can always attribute a specific reasons to it. I am then depressed because depressing things are happening, and it is an "appropriate" reaction. To go back to the beginning, understanding the obvious reason why you are currently depressed entirely removes the "this is a part of me" aspect. Nobody thinks a person mourning for a loved one suffers from "depression" as a condition, for example. I think I learned a new skill.
Second disclaimer: I can only speak for what I went through, and I am not a professional. It is entirely possible that your depression has other causes, and cannot be fixed by talk therapy. For some, knowing that it worked for me might instill hope, though.