So Frustrating

It may not be in your mind. Check into food allergies (IgG, not IgE - just tell your doctor and he'll know). Also look at celiac disease, gastro disorders, thyroid problems, hormone levels. There is often a physical reason for things most people attribute to psychology. If you were dieting or had been eating very little for a while, you could have shrunken your stomach and eaten away at the fat pad the protects your vagal nerve from pressure from the food you eat. This could make you nauseous after eating as well - the only remedy would, of course, be to gain some weight back, but this usually doesn't happen unless you have some pretty extreme weight loss. Look into functional medicine and find a practitioner who will look for alternatives with you if you are not getting the type of support you need.

I'm the same. I'm normal weight but almost every time I eat I feel sick. I haven't been 'sick' yet thankfully, but sometimes I'd rather hunger pains than 'eating pains'.

I don't feel over weight and I've always not cared about that.

If you ever find out what it is, please tell us

If you think you are fat you won't like your own body. If you attribute food to growing larger you will become more unhappy. So it makes sense to me that when you eat you think to yourself god I don't want to weigh anymore. But I am no doctor and good thing to, because if I was then I really wouldn't trust me :P