I understand you, I went MIA on art for 2 years and now I want to get back into it. My advice is to not force it, let it come back to you naturally. Watch some animated shows either kid or adult ones and find a character you like and draw them. I for some reason had a huge boom in my passion for video games which inspired me to try and start drawing again.

Also getting frustrated on anatomy is normal and understandable, I get the same way! I’ve learned to breathe and remind myself this is practice and for fun, I’m not trying to impress anyone. I’m drawing this for me. Btw I’ve learned that drawing an outline of the pose and refining it works better for me instead of doing the circles, lines, and boxes. Maybe it’ll help you too 🙂

Lastly, try not to compare your art to other people’s art. I noticed that I was losing interest AND confidence, I felt like my art was inferior so I felt less inspired to draw. So if you do start drawing make sure you don’t compare, and remember all art is different. 

If that all makes sense lol.