I had a friend that was the victim of such a situation. I say "had" because he ghosted me and all of his friends over it. It is very sad.
This friend arrived to our regular coffee get-togethers just beaming and on cloud nine one day, exclaiming he'd met someone and was very excited. The more he spoke the clearer it became: this "someone" was an illegal immigrant who was about to be deported. Friend was trying to figure out how he could help his new love, and at least had the sense to say he wasn't going to marry him... and two weeks later he married him. We all inquired if they had signed a prenup and, of course, the answer was no.
First it was the deportation issue, so friend spent (to friend group's best estimate) about $20,000 on the wedding and honeymoon, plus an untold sum on immigration attorneys. Then immigrant husband's substance abuse issues came to fore, and friend spent another $50,000 on rehab. Of course there was the wardrobe refresh and a lease on a new BMW, so there went another $50,000. Then immigrant's "brother" needed help, so friend paid for his flight, his immigration attorneys, put the "brother" up in one of friend's apartments (which meant the $2500 a month he previously collected in rent was never a question), and then, mysteriously, "brother" disappeared right after friend was burglarized (to the tune of $100,000 in stolen jewelry, art pieces and other valuables, which the insurance company fought and fought but eventually friend's attorney coerced them into covering).
It was at the point of the burglary that we sat friend down and showed him how his immigrant husband was robbing him blind. I'm sure that there was far more to the losses that friend suffered; he'd grown tired of our meddling and stopped telling us of his woes. We kept trying to point out to him that he wasn't happy in the relationship, that the immigrant husband spent more time with his "brother" than he did with friend, and that the burglary was just too coincidental to not be the "brother" in cahoots with the immigrant husband. Who else knew where the expensive pieces of jewelry were and most obviously, the precious and prized artifact that friend had cherished for decades? Even the police had told friend that it was an inside job. But no, it couldn't possibly be the immigrant husband's "brother" because (wait for it...) he was out of the country visiting their family (without a passport). Friend grew incensed that we were pointing fingers, and that was it; he ghosted our entire group.
The house went up for sale about a year and a half later. We don't know if the immigrant husband was still in the picture; neither he nor (former) friend had been seen in the usual haunts for months. The "brother" had gotten wrapped up in drugs, been caught trying to sell them, convicted and sentenced to something like 15 years according to the reports in our local news. We surmised that our former friend's immigrant husband was also involved but friend had bankrolled his defense resulting in the sale of his home.
We have no idea where our former friend is or what happened.