So, what from I read..
Della is very devoted, and might be difficult to define Della apart from Jim. Jim makes a sacrifice his watch to he can passed down to family generation, so he can give the watch to Della. (Della’s one devotion is less strange and kind of wonderful) and why? They both make a sacrifice their only prized possessions to get gifts for each other (just being random, if this doesn’t help. I’m sorry)