I live in a house with my partner and a roommate. She's great in almost every way except for when it comes to food: when she eats she chews with her mouth open (and lots of extra smacking), speaks with her mouth full, and eats with her hands. It's so bad that my partner and I have trouble staying in the same room with her when she eats. Her mastication overpowers a loud radio or TV, normal conversation, everything.

I was raised not to make comments to people about their manners - especially when it comes to eating - because it's the parents' job to teach their kids proper manners. Clearly this didn't happen with my roommate. I was also raised to be patient and forgiving, but she is constantly snacking - and smacking - from the time she gets home in the evening to the time I go to bed, and frankly it's affecting my own appetite and eating habits (I can't have dinner when she's home, etc.)

So do I talk to her about it (and if so, what's the nicest way of doing so?) or should I just continue to look for reasons to excuse myself? I know it's been damaging her love life and work possibilities, too.