It's a bad economy.
Many good people are under allot of stress due to it.
While its just speculation, this could be a very good possibility this could have been the cause for her to make a poor choice.
Much like the Kes we saw in "Fury", how ironic is it that Jen Lien has forgotten herself and lost her way?
She's not consistently been in the public eye for many years so we don't know what exactly happened, but I wouldn't be surprised that economic depression has exacerbated things for her household (and people have been affected much more badly in other cases, with murder or/and suicide occurring). I'm not sure about her black hair dye, but in her mugshot she seems in a much better state than she was last time in one of her rare public appearances (that '10 convention?). I'm sorry I was unintentionally tactless about her earlier appearances.
Anyway lets not speculate too much and I really hope things aren't crashing down for her as badly as they have been for Gary Dourdan, another person who suddenly dropped from a successful TV show, with his professional and personal life irreversibly going down the crapper much more publicly (he was arrested three times in recent years and this month filed for banckruptcy).