She either has...or hasn’t...violated US immigration/residency/labor laws or she hasn’t. Let’s see *all* the evidence.
It certainly seems that in her 47 years residing in the US that her spouse would’ve made an attempt to petition for her to get permanent resident status. That is, of course, there is something that has prevented him from doing so. Marriage fraud cases carry a lifetime ban if it is proven. Yes, she’s not a criminal just low hanging fruit. I wonder what brought her to ICE attention. It seems unusual that non crims like her would be targeted, but we don’t have the entire story. My guess and only a guess, is that she may have been required to check in periodically with ICE as many non detained cases are and somehow ended up in custody.