Looking for a Book: War Romance, Soldier Dies, Brother Raises Daughter, Addicted Second Husband

I’m looking for a historical romance—possibly published in the 1980s or 1990s—set across Europe, America, and London. The story starts during WWII in Europe, possibly Italy (or another European country). A young, beautiful woman is billeted in a house with military officers. She starts an affair with one of the soldiers, and they eventually marry and move to his hometown in America. In America, they have a daughter, but the husband dies in the war. The soldier’s younger brother, who also had feelings for the woman, helps raise the daughter after the husband’s death. He writes letters during the war, and remains emotionally close to both mother and daughter. Later, the woman marries a photographer (or someone in the arts/film/creative industry) in London. He becomes addicted to drugs, and she catches him injecting, possibly heroin. He also contracts hepatitis, and this causes major tension in the marriage. There’s a dramatic confrontation. The story eventually shifts perspective to the daughter, now grown up. She was raised by the uncle, and at the end of the book she returns to Europe (possibly the original country where her mother was from) to connect with her late mother’s past.