That’s what people do here too they work really hard and save up for a down payment for a home except they don’t get to live rent free so it takes them a lot longer and they have to work a lot harder and once they get their house they have to keep working they don’t just chill and play video games while they have a baby on the way.
You know what would be fair? Him selling HIS house and coming back to the US and never speak to Mary again. Maybe give her 10K for her to rent some shack for a while for all the trouble she went exploiting him for years.