Writers block

I had this specific idea and theme I wanted. Yet as much as I love writing I struggle with motivation and writers block much more than I do with other media. When I am drawing or sketching Idea's I am filled with so many ideas. 
What kind of character is this, what place is this. Like I am already imagining all of the ways I will write a story for the art I am drawing.

I become haunted by the narrative "A picture is worth a thousand words", and I am frustrated by the fact this only exists in my head. Why is it so hard to bring it into written word for me?
Am I afraid of critique? of being misunderstood?
Like I have to hold a readers hand and walk them through my entire thought process?

I don't know what it is. I just keep trying to do something but I am exhausted by my own personal cycle.

Make a new account, new media, new app, new document. Write something and spend hours immersed and completely fixated on it. Maybe this trend follows for a few days, but then....I wake up and suddenly that feeling is gone. The will and drive for it dissipated and now it's 3 months later. 
"Wow....you forgot this existed and lost interest again."
"When are you going to follow through?"

I know part of it is a vicious cycle perpetuated by my struggles with ADHD and social anxiety.
I just really really want to finally make something.
I am 28 years old now, two years from 30, and I have been dreaming about writing my own book, novel, graphic series anything! for years. Since the first time I opened this old game up  I use to play when I was....oh...maybe 12 or 13? It had a personal diary in it. I pretended to write entries for a character I made up in my head and that lasted for...well...a few days.
I tried again.
found something else tried that
Learned how to use microsoft word and wow I maybe got 8 chapters finally! and that was such a huge accomplishment for me at the time and since then.....I have never been able to write a full 8 chapters worth.
I rewrite, scrap, write it again, use a different technique, a different way of telling the story and.....nothing.

I thought maybe trying to tell a story that appealed to one of my autistic special interests on this platform through the blog entry format might work. In some ways I managed to put a lot of work into it and it was fun. (If you didn't know my special interest at the time that really inspired my other blogs on here was The Mystery Flesh Pit) 
I don't know if you could tell. lol
but while it worked it was once again short lived. The only difference is I still feel that tickle?
The itch in my brain to continue. Do more. Tell you more about the world I was in visioning.
Really bring it together.

I don't know.

All I can do is try.