I really do relate and identify with what you're experiencing.
It's a common thread that seems to bother most of us. It isn't "unique or different."

We can get into a mode of thinking "all or nothing -- either we're perfect or we're failing" and it will really kick us in the butt!
My head... just like a magnet... will automatically be attracted to negative thoughts... period. I haven't been able to "stop it" from doing that. (Is that kind of like "Powerless over negative thinking about myself?" )
Well... I'm powerless over alcohol... but, I'm not drinking... so, what is it that I'm doing that keeps me sober? I'm taking certain actions that lead towards sobriety and it keeps me sober.
So, how do I apply that principle to my possible condition of being "Powerless over negative thinking about myself?"
The answer: I must take positive actions that leads towards positive healthy thoughts about myself... or I will automatically slip into the mode of thinking negative thoughts about myself.
Remember our "gratitude lists"? That was an inventory of what we were grateful for. If we did the list daily... we got to feeling pretty good... and often, we got to feeling so good... that we forgot to keep up with the list. A few weeks or months later... we're down in the dumps and someone suggests "have you tried a gratitude list?"

We know that it works. It's the "continual doing" of what works that gives us the big pay off.
For me... two of my weaknesses have been discipline and structure. So, I have to "continually work towards" discipline and structure. One way that I do that... is with my daily Step 10.
How about a "positives list"? What if we got into the habit of daily making a list of "what's good about me"? What are my strengths? What are the pleasing characteristics of my personality? What am I good at?
By focusing on my strengths... my weaknesses automatically get taken care of. And, if I focus on my weaknesses... pretty soon, I won't feel that I have any strengths.
So, in my daily Step 10... I make inventory on my positives, my assest, and I ask myself "How can I improve upon these?"
For a long time, I had to post little post-its all over the house with reminders like "I like myself!"
I appear to be unable to "think" myself into positive thinking... but I can "act" myself into positive thinking. By taking positive actions, that leads towards positive thinking about myself... eventually I start thinking about myself in positive ways (whether I believe it or not when I start it).
And, for me... it requires that daily discipline of "doing it." I refer to it as my "Mental Training Exercises."
One of my major problems was negative self-talk. "My head tells me things that I don't need to be listening to!" Then, I would end up depressed, restless, irritable, moody, feeling stuck or anxious.
So, I have to "take actions" to counter-act the negative self-talk. Many of those actions... are not written in our book. They're little things like "When I see someone with a heavy load... offer to help them." When I'm in the parking lot of the supermarket... grab a shopping cart or two, and push them inside the store. When I see some liter... just pick it up and throw it away. Consciously "be nice to people."

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Sometimes... I really am walking around giving myself instructions to "be nice to people"... not because I'm a bad person, and not because I tend to not be nice to people... it's because my head needs to hear me saying "be nice to people". Later on... when I get an attack of "negative head" talking to me... there seems to be another side of my head that fires back with "that's not true! I go out of my way to be nice to people!" And, it happens automatically.
A different variation of the "be nice to people" is a "do something good for someone and don't let them know that you did it."
So... how do I incorporate that into my daily Step 10/11/12?
"In considering my plans for the day"

(that's my "To Do List") I add:
1. Be nice to people today.
2. Do something good for someone and don't let them know I did it.
3. Find some liter to pick up and pick it up.
4. (Then, I add my regular stuff like): Go to the bank.
5. Drop off clothes to the cleaners.
6. Balance my checkbook.
At then end of the day... "while reviewing my day"... I go over my list to determine how well that I did, and what I can do better tomorrow.
At the end of my "Step 10 Inventory" I'm feeling pretty good about me and I have a good nights sleep. I feel comfortable. At peace. And, this begins to affect my sub-conscious thinking and I have good dreams and wake up feeling full of energy, charged up and looking to jump into my list!
That's how I do it. It may or may not appeal to you. You may be doing something that already works better for you. I enjoy trying different things. When I hear of someone doing something and it's paying off for them... I like to give it a good honest try and see what it will do for me.
One day, here on the forum, someone posted a prayer, that was "God, bless me big time!" When I heard that, I liked it and decided to give it a try. It's been a few months now... and I'm still consciously saying "God... bless me big time!" It feels good when I do it. It causes me to laugh. It helps me to think positive. It helped me to change some more of my thoughts about God, and to think of God in a different way.
To help me try it and then make it a habit... I started by adding it to my daily "To Do List" (My daily Step 10 List).
Now... I could be doing my daily Step 10 like I did years ago... when I was "looking for the things that I was doing wrong and making amends for them" ... but, I began to notice, that "what I think about is what I tend to attract." So... if I'm "looking for my wrongs" ... I'll end up attracting more wrongs to look at!
Dallas