Wikipedia's English link is here, containing a fair amount of biographical detail. The German site is comparable, though the French and Italian sites are sketchy..
Feuerbach still seems to be well-regarded in Germany where his paintings can be found in major museums. Seattle's Frye Art Museum has a few examples of his work, and the "Old Woman Seated" painting shown below is at the Norton Simon in Pasadena, California.
This early study is in the Frye collection, thought I don't recall having seen it displayed.
Wikipedia calls this "his first masterpiece." It was painted in Paris.
Feuerbach painted several self-portraits around that time, this being the most dramatic.
A nice study, not at all Classical.
She was his model in Italy for several years. His painting Ruhende Nymphe (Peaceful Nymph), a nude work that's not office-safe looks like it might be her, but is listed as a 1870 work -- probably after their relationship.
She was a strong supporter of Feuerbach.
A major painting. The German title might also be translated as "Plato's Banquet" (Austrain dialect).
The first biographical link above, in reference to this ceiling painting, states: "In 1873 Feuerbach became a professor at the Vienna Academy of Fine Arts and painted for the academy building Fall of the Titans, generally regarded as his weakest work. Ill and discouraged by the harsh criticism of this work, Feuerbach left Vienna in 1876 and returned to Italy, where he died."