From excitement to depression
This is a sad tale of a woman who super-excited to leave county jail but fell into depression. She only served a six-month sentence but was ecstatic to be out and free. However, not long after, the excitement wore off, and she became depressed over time. The OP, who used to work at her jail and visited her often, said she was happier in jail than out.
We can’t even begin to imagine what sort of emotions go through the minds of someone who’s been in jail, even if it was a brief half-year stint. We hope she gets better and finds excitement in life again.