People will say any car that isn't an everyday run of the mill economy car is just because you have a small penis. They're just jealous that you have more money than them, or have modified your car...
How do you know she's not a slut? Did she tell you that? If my gf of 3 months was getting BBC on the side I would be very skeptical that she's not slut
In America people will generally be jealous and angry at you, hence the insults and whatnot. It's very common in asian countries to have a wife/girlfriend half your age