True Blue

This sounds too messy. He doesn't want the ex- wife to know about you, the family does't know he's not married any more, so where does he live? Where does the family think he goes home to every night? If he's not married then he shouldn't be afraid to tell the ex about you especially since he has a son and he's ready to marry you. Secondly, I'm concerned with his eagerness to leave the country and his son behind. I see a few red flags here. I agree with Swedish, three months is way too soon to marry someone, let alone some one with all the baggage and drama this guy has. I say run to the airport (ALONE) and don't look back.

One more thing, there's such a thing a court ordered visitation so if he's really concerned with the ex preventing him from seeing his son he can take her to court for visitation. However, it sounds like he's really not that concerned about seeing his son if he's ready to leave everything and everyone behing to follow you to another country.