Look I get you were annoyed but I feel bad for her. She shouldn't have put the honey on the dummy, but the risk of botulism is extremely low to non existent. She clearly felt terrible, you have deliberately ignored her so her anxiety and guilt has escalated. She obviously cares for you and your child.
Sorry but I think while she shouldn't have done it you've also handled it badly. You need to either end the friendship or get over it and have a cuppa and a chat.