The actions of human beings can be cruedly classified
into either those that increase pleasure and comfort
or those that minimize pain, but you could argue
that these are one and the same. It is a very simplistic
way of viewing humans, but long have I seen myself and
others as mere animals -- that is, through animalistic
lenses. Every action, to some, seems to have a biological
reason, but there are a lot of gaps to this line of
thinking. Human emotions are largely illogical, and
human thought is similarly unexplainable. Innovation,
compassion, and so on, have more to do with our role
in a community than with our interpersonal relationship.
It made me think, where, in this idea, does the
concept of sacrificing yourself to a loved one fall?
You are increasing your own pain, and certainly not
adding to your own comfort, unless you consider the
safety of a loved one to be a contributor to your
wellbeing, which, if true, isn't something you can feel
after death. What do you think?

P.S. Some Things We Do by Swans is a song I love for this
reason.