I am going to play advocatus diaboli here.
By giving her a short sentence, she actually gets punished more. After all she screwed family and friends. So she has to live with them and the shame and possible retribution.
If she comes out of prison 20 years later, half of the relatives could be dead. So she gets no shame, nicely tucked away in a prison. Now if a victim wants to sue or harm her, she will be out soon.
They will never get their money back anyway. The broad public wasn't harmed, so why should we the taxpayer pay for an extended punishment? In prison she earns like 50 cents per hour? So it would take a while when she can pay the victims back. On the other hand outside if she earns anything, 70% or so can be taken away for payments...