I agree with Eliot, it's horrible English. However, I think Meredith is implying that it's fortunate that John is so pretty/nice/good-looking/friendly (whatever) because it almost makes up for the fact that he's said something so utterly stupid.

The whole dialogue makes no sense whatsoever. Apart from that, the English is pretty bad, too.

This context is not broad enough to understand the implications, i.e. why Meredith calls John lucky and pretty.