When you think about it, "Resume" is like a shopping catalogue of ways our speaker could end her life. It's got options, short analyses, and even a suggestion about the best way to proceed. With this, Parker stages a fairly common (if morbid) version of a person's thought processes. When we're trying to decide whether or not to do something, we like to take time to think out all of our options. Sure, overall, this poem isn't even close to picking out flavors at Baskin Robbins. But in many other ways, the process of decision-making is identical.
The speaker is determined to choose the easiest option, and she concludes that living is easier than dying.
The end of the poem offers no resolution. Our speaker hasn't decided to live – she's just temporarily run out of options for killing herself.