I don't know if this helps but I was given this advice.
Write on a piece of paper the following:
"I AM AN AMAZING PERSON LIVING AN AMAZING LIFE IN THIS AMAZING WORLD. EVERYDAY I ATTRACT ABUNDANCE AND PROSPERITY".
Below it write 3 minor adjustments that you will do everyday to help to improve your situation.
P.S.
I know I will probably get the evangelistic approach comment once again...but what if it works?
The concept is right..ie you need to change your thoughts to change your emotions... but what you think has to also be "true" and believable. So, for most people with depression, your "mantra" is just too far from their experience/ feelings to be able to connect to it.
and the person with depression runs the risk of just "stuffing" down their emotions, which is likely how they got into the problem in the first place. So, something more realistic might be "no matter what I feel, I offer something unique in this world, and no matter how hard my life is at the moment, this time will pass and I will find the strength to endure".... or something like that. Its probably still too far beyond what a depressed person could believe...
Getting over depression is about taking baby steps but also being honest with your feelings.
to give a practical, real life example (apologies if I shared before... I did check quickly and couldnt find it earlier in the thread)...........
All my life, I had assumed that people didnt like me. Even my best friend.. I thought she was just my friend cause she felt sorry for me... its sad, I know!
So, when I met new people, I was very reserved/ standoffish, cause whats the point in being friendly to someone who doesnt like me. As a consequence... people didnt like me! Vicious cycle.
In the middle of my "course" of counselling for depression, I did a business trip to the US, where I was going to be meeting lots of different people for the first time (both personal and work contexts). My counsellor and I decided to use this as an experiment. So, I tried to consciously think "the people I meet are going to like me", everytime I went into a new context. (it probably wasnt even quite so positive as that, but it gives you the idea). I was honestly amazed at the difference in my approach to meeting people, and their response to me. Just by changing my self-talk, I changed my behaviour and the response of the people around me. it was a great example to me of how changing something so simple could have a profound effect.
But I think the strength of it was that it was something I could honestly connect with... not just generic "power of positive thinking"