Comment by gwbas1c

"East Germany" fell apart because the people stuck there quickly realized how "ridiculous" it was. (See the post you replied to.)

There was a lot of contact between West and East Germans due to the awkward nature of the division of East and West Germany and East and West Berlin. In contrast, that contact doesn't exist between North and South Korea.

(Remember, West Berlin was an enclave inside of East Germany, and West Germans were allowed to travel through East Germany in order to travel in and out of West Berlin.)