How do Jean Valjean and Fantine parallel one another and how do they differ?
Valjean and Fantine are cursed by two things: one, situation in life; two, bad decisions. Valjean was forced into a situtation of poverty and starvation by forces outside his control. However, he made the bad choice to steal, and even more so, to try to escape prison rather than serve his time and be done. Valjean is judged for his past actions even though he has paid his price.
Similarly, Fantine is forced into a situation of having to prostitute herself to support her child. She is not in control of the judgemental behavior of the factory manager who fires her. However, she made the bad decision to trust the man who impregnated and then deserted her, and to trust the Thenardiers, who are extorting her. She is trying to atone for her bad decisions and be responsible, but the bad behavior of those around her are blocking her path.
The main difference between the two is that Valjean finds salvation in the Bishop, and is able to move forward. Fantine only meets the kindness of Valjean when it is too late to turn things around.