Final answer:
It is generally simpler for an ex-partner to establish clear boundaries after a relationship ends to minimize emotional and social costs, as maintaining a complex relationship or nurturing continued emotional involvement may have higher costs and fewer benefits.
Step-by-step explanation:
The question explores what may be simpler for an ex-partner after ending a romantic relationship. Considering people as naive economists, we can assume that individuals keep track of the costs and benefits of maintaining a relationship. When a relationship ends, it often becomes important for individuals to establish clear boundaries to minimize the emotional and social costs of continued interaction. This means that instead of maintaining a complex relationship or nurturing continued emotional involvement, which are likely to incur greater emotional costs and provide fewer benefits, setting clear boundaries can simplify post-relationship interactions. Likewise, pursuing shared interests may also pose challenges, potentially creating unwanted complexity due to overlapping social circles and emotional entanglements.