The "Art" of watching someone's back while still guarding your own...

It seems to me..
that a very delicate balance must be reached while watching someone ELSE's back...
so as not to lose track of one's OWN protection mechanism....
Life is filled with overlapping influences....with conspicuously related events...
some perhaps NOT so conspicuous...
But frequent "grey-mattered" questions  of priority continue to rear their ambiguous heads...
For example:
One may give their word to care for another, to "watch his or her back", as it were...
and this oath may very well become more than just a commitment...
It can become more of a CAUSE...a Raison d'Etre...
And somehow, amid the epic and arduous building of said "cause"....
the great "protector" looks up and discovers that he/she has lost his own balance somehow...
Am I making sense ??