I've been planning a fictional universe for my novel for many years now. I really feel like I want to write the story, but I have two main problems. The first is that I have OCD, so I feel like I have never done enough background planning and never feel like it is the right time to begin writing any scene. I especially feel this way about the characters, because I don't want them to all sound the same and have 0 depth. But the problem with planning is that I always get way too bogged down in the details (again, an OCD trait). This perfectionism/need to plan everything down to the last detail serves me well in other areas of life (I am currently a 2nd year M.D. student and do very well academically), but with writing I feel like there is simply no way I will ever bring myself to actually start writing. Because of my busy school schedule, I have very little free time, but I've spent a large percentage of it over the past 2 years planning the background (characters, setting, etc.) for my story. I've even consulted astrophysicists on minute details about the various planets in my story (stellar classes that work for habitable planets, weather/climate issues, working out specific mathematical variables to make them seem realistic). Also I feel like when I do try to write, I have absolutely no ability to describe settings or characters. I've tried reading books like "Word Painting" by Rebecca Mcclanahan but the instructions therein seem way too esoteric for me. I suck at writing, which is a shame because I really want to write this story someday.