I wouldn't. I would politely decline and say I wasn't hungry but thank you.

Heck no! Rotting bananas and insect infestation in the kitchen point to a serious lack of hygiene practices. Not only would I not accept the banana bread from her, I would make an urgent mental note not to eat anything prepared in her kitchen again.

And remember, if any of her cereals or grains from the pantry have odd little things that look like grains of rice, DON'T eat them!

http://upload.wikimedia.org/wikipedia/commons/4/4c/Drosophila_melanogaster_-_side_(aka).jpg

Probably not. I wouldn't say why, of course. I'd just decline without giving a reason. If she presses, I'd just say I already ate.

I wouldn't, however, make any judgments about her other food. Maybe she just forgot about the bananas this one time. It's possible, especially now when there's so much stuff to cook.

In Summer where I live a banana on the bench can go from green to black within a day or two, I'm not kidding. And bananas do have a pretty thick peel. One of the things you do with old bananas is cook them. Put them in cakes or bread. I wouldn't use a really old one to make a smoothie but the older they are the sweeter they are - sort of makes sense to leave them until they are at least ripe to cook them. BUT there are limits!

If they were really off and smelly and the fly had obviously been there for days and beginning to breed in that soft googy mush, then no. I wouldn't eat the bread.

I guess fruit fly eggs would cook and die at the temperature the cake was cooked, and the bad bugs would be destroyed but maybe not :)

I'd use the bananas in these pictures to cook in bread or cake, even the blacker ones as long as they weren't rotting
http://www1.istockphoto.com/file_thumbview_approve/524868/2/istockphoto_524868_ripe_banana.jpg
http://k43.pbase.com/v3/82/308182/2/48788242.Aug_MG_5063160001s.jpg

THESE ARE TOO RIPE and I wouldn't use them, see how they are rotting on the ends
http://www.virtualantarctica.com/efa9901/images/black_bananas_border.jpg

Yes. It's been cooked and the way-too-ripe bananas taste better in bread.