When I was a kid I found I couldn't leave my bowl of cereal alone or I couldn't eat it. If i was present and watching it I knew nothing bad had happened to it, If i left it for any reason my mind would suggest all the things that could be in there that I couldn't see, typically worms, and I would have difficulty choking it down. As an adult, this has morphed into, i see something i find gross, (worms and house centipedes mostly) the next time I go to eat my mind will give me vivid images of finding, ( or worse, NOT finding) those things in my food to the point where even if i do manage to put the food in my mouth I'm fighting my gag reflex to swallow and keep it there. The result is that I won't/can't eat the rest of the day and only manage light amounts the next. Extreme distraction at the time of eating helps, watching a isn't typically enough but reading a book or very compelling or passionate conversation can. Why does my brain do this to me? Why does it hate me? How do I get it to STOP? I have a very fast metabolism and am already teetering on being underweight.
The kind of experience you are describing is not unusual, but it is not a typical food addiction or eating disorder problem. The thoughts may be something that are called obsessions and might be relieved with a medication. Working with a therapist who specializes in cognitive therapy will also be helpful. The problem is solvable with the right approach of behavioral medicine, but is not something that you can just figure out on your own or with suggestions from well-meaning friends without the right training. Make an appointment with a psychiatrist who will assess the situation and help you form a treatment plan that will solve the problem as quickly as possible. There is no need for you to continue suffering with it on your own. The treatment plan will include specialized therapy and perhaps medication.