After being really blown away by ^ that drawing, then reading what you wrote… I want to grab you by the shoulders, shake you side to side like a maniac and yell “you can’t quit now!!!”.
I mean, Your gonna do what your gonna do, but I hope you don’t quit drawing, you can totally draw!
Apologies if any of this below is already known to you, or that you’ve already tried it ect. :
I know the feeling with capturing likeness’. Pain in the ass, biggest thing for me was being able to draw really lightly and using a stubby pencil held kinda sorta like this:

I sometimes draw with a grid if I’m a wuss, or my other wuss technique is I will sketch the face out as best I can then scan it and overlay the scan over the photo in gimp and shuffle between the layers to see where the drawing is wrong and the photo is right and take the sketch out of the scanner and correct it accordingly and then repeat until I’m satisfied.
I also stopped drawing on printing paper with pencil crayons. For me, the supplies DO matter. I like watercolors and inks and watercolor markers, moleskine paper for inked drawings because its smooth, erases well and is off white so it scans more accurately as long as the drawing has a good amount of contrast. And it just feels good to draw on that paper. Haven’t found the right watercolor paper yet. I’m single, so my moneys go to the art supplies. My skills are not yet where I wan’t them to be just yet but it gets better year by year, I just want to make good art so I keep at it, who knows how much time I have in the world…
To me it looks like you can draw no prob, but need to try some different rendering techniques for color, and maybe try your own interpretations for some characters so you don’t always have to worry about likeness if it stresses you out. Maybe you could color them digitally? I’ve scanned some of my drawings before then on another piece of paper painted abstract watercolors and scanned those then used the watercolors underneath the pencil lines of the drawing in different ways to ‘color’ it in gimp.
Never give up, never surrender.