The one(s) she lives for

For 25-year-old Celia the most important person in her life, the
one she lives and would die for, is Peter.
They met four years ago and have been living together for two
years.

For 45-year-old Celia the most important people in her life, the
ones she lives and would die for, are her, uhm, "our" three
children.
Yes, Peter is a wonderful husband.

For 80-year-old Celia life has lost its beauty and meaning since
Peter died. It's no secret that she'd rather join him. Her three
children, successful and parents themselves, try to come to terms
with her (mental) preparations to leave.