If these poems are so funny, does that mean they are satirical? Unfortunately not. It seems that the comedic tendencies of the poet are actually darker than just to criticize. In this case, the truth of the matter seems to be that the poet has become so chronically heartbroken and unnerved by her brother's spiral into severe drug addiction, that she has become somewhat detached from the situation, and the humor is simply her way of trying to make sense of the challenges the family faces.
In other words, these poems are a picture of the way drug addiction affects one's community and family, and the thesis of the poetry could easily be just that: The poetry says, "We all suffered because of his decisions, but ultimately, it's because we love him that it hurts." And it also shows the full spectrum of emotions that are contained within that broader perspective. With the true care and love for her brother, the poet is forced to suffer his painful fate with him.
Also, it isn't like drug addiction just randomly sneaked up on their family. As a historically disenfranchised people group, this Native American family is limited to the brokenness of reservation life, and drug addiction is a serious problem in many of those communities, so this poetry is not limited to its specific value as a human response to suffering (it is that), but it is also a reminder of the chronic problem of disenfranchisement and the way that it can often lead people to extreme behavior, without the structure of a meaningful, oriented life.
When a person begins to slide into chronic terror, their options become limited, and for many people, paranoia, hopelessness, and depression can become terrifying, especially since there isn't really a good way to explain those invisible problems. To say, "This guy is just a drug addict," would be the same as ignoring the whole of Diaz's poetry—she is clearly trying to remind her reader that these issues are complex and intersectional.
