I'm going against the flow here, but that's no so unusual, and some of the comments have already alluded to this.
I hope what I'm going to say does not sound harsh or unsympathetic - I'm just trying to answer this question as it is posed. It also possible that I've missed the mark entirely. Questions like these are often difficult to grasp and answer correctly.
This whole question revolves around "I tried to learn this... I tried that... still not getting it... Have trouble with the scales, with the theory..."
But I see something missing here: Maybe it's so simple it needn't be stated, but it sounds like your technical and intellectual failures are your main concern, while a musician's concern is always "I can't hear/perform/write the music."
I think the problem is that you might be putting "the cart before the horse". Before you try anything, you have to first TRY YOURSELF:
If you have an urge to create music, then you must have music inside of you that wants to be expressed somehow - that's where that urge comes from. Something inside you is inspiring you and producing that urge. So before you do anything - decide on any style or genre or method - you need to discover the music that is inside of you.
This might sound very philosophical or abstract, but it really isn't. Listen to music that moves you and inspires you. Sing it over to yourself and digest it - emotionally and sensually - not technically. Hum and sing to yourself that music and expand on it - improvise on it - without any instrument - learn about your own musical mind and sensibilities without any instrument or genre or technique or method.
By doing that, you will discover your own music. Then you must go back and discover which genres and methods will help you to achieve the ultimate goal of every musician: To play and write your own music.
Maybe you need to know lots of scales and theory for your music, maybe you don't. Maybe Flamenco is your thing, maybe it's not - that's all up to you and your music. The problem is not that you're not grasping scales or chords because you don't have a teacher. The problem is that you haven't yet grasped your own music, and what you need to do to make it a reality. Certainly you need a teacher, but before that you need to identify your inner musical urge.
I grew up surrounded by music - jazz, classical, early rock n' roll, show tunes. I began hearing my own music at a young age. I think many of us who are serious musicians share such experiences. That doesn't mean that you can't start later - but you do have to start at some point if you want to make music and not just "operate the guitar".
This tipped me off to the possible problem/solution:
Ten years ago, inspired my Mark Knopfler, I picked the guitar. Had no
plans becoming a professional musician, just in order to create music
for myself. I started learning Flamenco...
Question: If you were inspired my Mark Knopfler, why did you start learning Flamenco? Why not start with the music that inspired you? (Mark Knopfler's music is also a lot easier than Flamenco). Along those same lines, this question continues.
As I read the question further, I became more and more convinced that was the problem: @Mark2Bra doesn't really know the music he wants to make, so it's possible he'll spend his whole life trying and failing. He's attacking it from "the outside in" - trying to learn flamenco and scales and theory and digital piano - but what good will that do when he hasn't yet listened to himself?
That being so, I can't agree with answers that are trying to fix certain manifestations of a more fundamental problem, although all the answers contain good advice.
Now, i don't believe in the music talent myth
Please explain what "music talent myth" you are referring to. I know of no such myth. I do know that some people have more musical talent than others, just as some people are better athletes than others, or better writers or better painters.
Perhaps your insistence that "you don't believe in the music talent myth" is part of your problem: If you don't believe in your our talent, you will never try to discover it. That's why you are taking what appears to be a mechanical approach to music: You don't know or understand your own talent and you don't believe in "musical talent": Therefore you think that if you go through the motions as prescribed. you should get the desired result: Just like when solving an equation. But making music is not like solving an equation: It's an expressive art form, not a mechanical or mathematical process.
Further - Quoting your question:
Operating guitar for 10 years but can't make music.
Nobody operates a guitar. We play the guitar, we don't operate it.
For a musician, a musical instrument is not a machine or some cold distant object that needs to be operated by following a set of instructions. It's their voice, and true vocalists are also musicians. One listen to Ella Fitzgerald proves that. Musicians don't operate their instruments - they play - any more than vocalists operate their voices - they sing. If you watch the great players, their instruments are extensions of their bodies, used for expressing their music. They are not devices to be operated.
No operations going on here:
I have a strong spatial intelligence - I think in pictures and have a
relatively good memory for I can recall memories by "looking at them"
What does any of that have to do with making music? I don't recall ever hearing or reading that a great musician or composer was blessed with "strong spatial intelligence".
As for "thinking in pictures", perhaps that's not the best way for a musician to think - many of our great musicians were blind, and music is about sound and feelings, not pictures.
Strong spatial intelligence and thinking in pictures would appear to be great strengths for an artist or sculptor, not a musician. I am not saying you don't have musical talent/aptitude - many people are blessed with multiple talents. I'm just not sure what those abilities have to do with making music.
This leads me back to the impression I'm getting that you have not yet heard your own music, and so you're not taking a musical approach to your musical endeavors. When you discover your music - tap into your own musical talent - your own inner musical ear - you will not be talking about "spatial intelligence and thinking in pictures". You will be talking about sounds and feelings and how to create them and capture them.