Complex sentence: When Booth Luce received the picture, she was so offended that she seriously considered destroying it; but instead she simply locked the work away, until decades later anonymously donating it to the Phoenix Art Museum where it remains.
Split into simpler sentences: When Booth Luce received the picture, she was so offended she seriously considered destroying it. She simply locked the work away and decades later anonymously donated the work to the Phoenix Art Museum where it remains.