I've gone through a similar process. For me what you described of splitting it into the tangible parts helped a lot - I'd spend a week just working on the back-

I've gone through a similar process. For me what you described of splitting it into the tangible parts helped a lot - I'd spend a week just working on the back-end and then a week on the front-end and vice-versa. Was hard to context switch between the two (especially as my back-end is usually python and front-end is usually a flavor of JS).