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I have a friend who I'm very close with and this has been something that truly, truly bothers me since I've met her. I've known her for about 4 years now and I have never gathered the courage to tell her that the way she chews is loud and obnoxious.
Once she was having an altercation with a coworker and complained to me about it. The coworker told her that she smacks her teeth when she chews and it's so loud. My friend said "I don't think I do that" and since she was so upset about the situation I said "maybe record yourself and see?"
I know, that's a lame answer.
Then one time she was chewing incredibly loud and I said "hey you're kind of chewing with your mouth open" and she proceeded to not do that for the next couple minutes but then soon resumed.
Then another time we were with another friend who also said she could "hear her chewing right in my ear" but didn't say it to her.
I know she's not doing this on purpose which is why I would feel terrible bringing it up. She's so self conscious as it is, I don't know how I can break it to her, especially after 4 years of not saying anything.