Feynman's first wife.
Feynman was like an reversed Stephen Hawking: he married his wife knowing that she had a serious illness, while Hawking's wife married him knowing that as well.
Just that in Feynman's case, the disease outcome (tuberculosis) was much more uncertain, and she tragically died much earlier, while Hawking with his certainty of decline lived much longer.
Reading about her death e.g. at Genius: Richard Feynman and Modern Physics by James Gleick (1994) is a major tearjerker, it's just too horrible.