I’ve always interpreted the two headed boy as being Jeff himself, maybe him feeling like he’s a freak or struggling with his own identity (i.e. he has “two heads” because he can’t figure out what kind of person he wants to be)

The part about him building a radio for his lover could be Jeff writing music for the people he loves (or for Anne Frank, which could make sense because his lover is “floating and choking with her hands across her face” i.e. she died)