I'm glad you liked "Happy Birthday"! It's probably never going to be one of my favorites, but I'm still pleased that people enjoy it.

And yeah, some stories are just really hard. Sometimes I find that's because I'm attacking the story from the wrong angle; sometimes it's because it's genuinely tough to get into certain characters' heads or figure out their motivations. Either way, I'd love to see you finish both those stories, especially the Eleven/Martha/Mickey one.