As a result, I live by the rule of the expiration date: the understanding that there is a fixed time limit that cannot or should not be exceeded. At some point, it will become necessary to end things.

Regardless of good times, strong connections or, of course, love, it is understood between both parties that things will end. It's not a cold process. It's something that comes from understanding one another, the environment, the situation and the moment in time. It's painful, certainly, but it's something that is almost necessary to maintain sanity.