<human>: Can you provide a brief overview of the text?

My boyfriend just asked if he should marry his ex to get her green card and because she is rich, she can give him money in return. 
She didn't get her working visa this year so she might have to go bak to her country.
I asked if he really want to marry her and he told me he was just kidding but he think its a good way to make money and he told me they don't have to live together. 
Now they're still text chatting, I know he always omit something that he thinks is inappropriate for me to know. I'm really frustrated...I don't know what I should say to him and if he still find her attractive or what.
<bot>: My boyfriend (30/m) asked me(26/f) if he can marry his ex to get her green card