The speaker is wondering whether pain could be packed away and a different, lighter self put on. The "dark rain" is a striking image for sadness or hurt, something that has fallen on them for a long time. They imagine putting all of it back in a box, as if it were something that could be stored and shut. Then they picture playing "a poet of insipid ruins," a role that sounds deliberately dull and faded, a person who writes about broken things without really feeling them.
The poem is a single question, and it never gets an answer. That gives it a wistful, tentative mood. The speaker doesn't seem sure that this plan would work, or even that they would want it. Living "only on the road" suggests constant movement, with no place to settle and nothing to hold on to. It might bring freedom, or it might just be a way of running from feeling. The title, "Betterment," sounds hopeful, but the poem leaves us wondering what the cost of feeling better would be.