Simone died of embarrassment because Bradford caught her boyfriends caught her cheating. The last of them being their grandfather, Bradford Stamper, an artist less famous than Simone. The adults she divorced and the elders died of overexertion. She married 2 adults and 3 elders after in hopes to give her twins a father figure. Ted died early too, because he is an alcoholic. She didn't get to have Weston's kids because they were both poor and young professionals back then, one of her biggest regrets in life.
Simone then married Ted Stamper, Weston's twin after he agreed to be her sperm donor. Mira was so dedicated to Simone that she burned him out of guilt and then offered her life to do all kinds of work for Simone. Her second husband, Kaveh, cheated on her with her mentee, Mira Kano. Simone truly loved her first husband, Weston Stamper. Simone, the Pablo Picasso, of this world aka Black widow attends her niece's wedding to give her tips as to keep her husband alive. My sim from my second generation, Simone, finished this successfully. Sims 4 had this black widow challenge where one must outlive 5 spouses.