Sacrifice is when one selflessly gives up something in service or deed for the undeserving, expecting nothing in return. It is selfish to desire anything from sacrifice. However, selfishness in its honest form is just.
Giving one's partner first priority is a choice not an obligation. Under the right circumstances we tend to give more than others deserve. And when they don't appreciate it, that's okay; people are prone to take that which they are not entitled to for granted.
Sacrifice is when one selflessly gives up something in service or deed for the undeserving and expects nothing in return. It is selfish to desire anything from sacrifice. Selfishness in its honest form is just.