WASHINGTON – Elizabeth Edwards, a senator’s wife whose life was shaped by loss — first of a teenage son, then of her husband’s two presidential campaigns, then of a marriage torn by his infidelity — has died.

Her health was a sad footnote to two presidential campaigns. She was diagnosed with breast cancer the day after the 2004 general election, a Republican victory that spoiled her husband’s chance to be vice president. In March 2007, during her husband’s second campaign, doctors found the cancer had spread to her bones and was incurable.

“The days of our lives, for all of us, are numbered,” Edwards wrote on her Facebook page Monday. “We know that.”

In her April 2010 afterword to “Resilience,” Edwards said she hoped for eight more years, so that she could see her youngest, Jack, graduate high school and perhaps have Cate, her oldest, give her a grandchild.