This started happening to me, just today. I shared a photo in my gallery, selected two recipients, verified that I chose wisely, sent the message and it went to someone entirely different! I closed the app (using the stock messaging app), tried again and my phone sent it to the same (wrong) person again. So, I started inside the messaging app and sent the image to just one person at a time, and that worked. Then, I started a brand new message to 'Erin', and just 'Erin', sent the message and couldn't find it in my message list because it's showing up under a totally different conversation thread with 2 other people and no mention of 'Erin', though she responded accordingly. What is going on?!?!?!?!?