I started my first draft in November last year, and I'm probably around halfway done. However, as I've been writing, I've come up with a lot more characters and subplots which I want to include in the book. The problem is, I haven't figured out how a lot of these subplots end, as I originally didn't intend for them to take up so much. I've been struggling with this for days, and I'm barely getting any writing done. I don't know what to do, so if anyone has any advice, I'd love to hear it.