I have a problem. Clearly many, but I'll get to the point. I don't know how to refer to different people saying direct speech in this excerpt. Should I set it out as is: or should I set it out like this: I'm thinking the latter would make more sense if the MC was actually looking at the crowd, but she's not. She's only hearing it, so would I go with the first one or write it out as if she's hazarding a guess by their voices?
The first example is cleaner, and I prefer it. I've seen that approach done before, and it's always clear to me that the author is presenting a handful of overheard comments. If there is something in particular that needs to be stated about an overheard comment, then you might expand on it as you've done in the second example, but if you're just present a series of snippets of conversation overheard by the character, I'd go with the first method.
If she's guessing I'd rewrite the second to include that she's only assuming that someone is disinterested and imagining a headshake. Right now it's too factual. But the first is fine. It all depends on what you're going for, and what tone you want to bring in by her imagining these details. Does it make it more excruciating? Is she a person who would do this?
I like the idea of imagining the actions. Sound better or too melodramatic? I may just go with the first if I can't manipulate it the way I want to; I can always change it later.
I agree with the first example being better, but if you feel it isn't clear enough, you could always use a simple reference tag on the first piece of dialogue to signify its source, such as, 'they began to mutter.' I gulped, hearing individual whispers from many unfamiliar faces. However, this sentence alone suggests that the character is listening to many whispers, so I think your reader would most likely understand what's going on.
I'd maybe do a mix of the first and second. I like the idea of her wincing as she imagined a head shaking. And pity dripping. But I'd rework that image. But the first speech tag One of them etc - didn't feel like she was imagining it and it didn't seem like info she could get without looking.
I gulped, listening to the whispers of unfamiliar voices behind my back. Imagining their sneers and faux pity. That’s Cat, isn’t it; the one who gave Alaska a love letter? I’m envious. I wouldn’t have the nerve to approach him, let alone give him a letter and watch him reject it in front of me. Poor girl. Perhaps something like that?
No. Please no. Please please no. Don't use italics for speech just because you'd don't have a name to attach a speech tag to. No, no, no, no, no, no, no....
Maybe adding the thoughts of MC? I gulped, hearing individual whispers from many unfamiliar faces. “That’s Cat, isn’t it; the one who gave Alaska a love letter?” I groaned inside at that, wondering if I was ever going to live this down. “I’m envious. I wouldn’t have the nerve to approach him, let alone give him a letter and watch him reject it in front of me.” I could picture the head shake that comment got. And the malicious glint in their eyes, too. “Poor girl.” I continued walking, leaving the comments, and those making them, behind.