The flashbacks and present day have such different tones
The flashbacks are dead serious and bleak, but then the present day stuff with the adult versions is halfway comedic, especially the stuff with Shauna and her husband, it almost feels like a romantic comedy at times between them.
Such an odd choice to make, i mean since young Shauna in the flashbacks is very serious and never goofy or quirky at all, just doesn't even feel like the same person when you go to the adult version.
Then you got the stuff with Misty and Walter which is even more comedic.