Are Lynne and her friend completely naked? It's difficult to tell. I know it's hot but being completely naked might not be totally necessary. Both Lynne and her friend seem to like the comment by smiling at him, giving the impression that it was a lovely thing to say. The husband then goes off to the front of the house to meet another unnamed woman to finish his sentence. What he says is in bold and italics, meaning he is both shouting and whispering those words.
What sort of town is this? Everyone under the sun is having an affair at the drop of a hat. This man has a wife who gets naked in the back garden but he is more than happy to find another woman to perform sordid sex acts with. We can only assume that his wife is denying him any sexual activity, but still isn't an excuse. And how long has this woman been waiting outside? Did she come round and then the husband said 'Hang on a minute, I'm just making my wife and her friend some iced tea and I'll be right out.' And he's about to go off in his vest and shorts with this woman? She's certainly kidding herself. He's not going to leave his wife, that's for sure.