While lots of research has explored how to prevent maintainers from abandoning the open-source projects that serve as our digital infrastructure, there are very few insights on addressing abandonment when it occurs. We argue open-source sustainability research must expand its focus beyond trying to keep particular projects alive, to also cover the sustainable use of open source by supporting users when they face potential or actual abandonment. We perform an interview study with 33 developers who have experienced open-source dependency abandonment and analyze the data using iterative thematic analysis. Often, multiple strategies were used to cope with abandonment, for example, first reaching out to the community to find potential alternatives, then switching to a community-accepted alternative if one exists. We found many developers felt they had little to no support or guidance when facing abandonment, leaving them to figure out what to do through a trial-and-error process on their own. Abandonment introduces cost for otherwise seemingly free dependencies, but users can decide whether and how to prepare for abandonment through a number of different strategies, such as dependency monitoring, building abstraction layers, and community involvement. In many cases, community members can invest in resources that help others facing the same abandoned dependency, but often do not because of the many other competing demands on their time – in a form of the volunteer’s dilemma. We discuss cost reduction strategies and ideas to overcome this volunteers dilemma. Our findings can be used directly by open-source users seeking resources on dealing with dependency abandonment, or by researchers to motivate future work supporting the sustainable use of open source.