I think she had a severe eating disorder myself. But nobody's perfect. She lived during a difficult time of plagues, wars, civil wars, even waring popes. She defied her parents who wanted to her to do what nice preteens of her time did - marry well for the family and instead went to live with a bunch of other defiant independent women who took care of people no one else would. She told the pope to grow up and come back to Rome and do his job. She even defied her own confessor who tried to get her to eat for her own sake and that's probably what paralysed and killed her at age 33.
She also told a lot of people that God loved them. An important message that could have gotten lost in the midst of everything else.
"Strange that so much suffering is caused because of the misunderstandings of God's true nature. God's heart is more gentle than the Virgin's first kiss upon the Christ. And God's forgiveness to all, to any thought or act, is more certain than our own being."