they know who they are and I don’t. I’ve spent a long time trying to twist myself into fitting in I have forgotten
This is where your anxiety comes from. Imagine if you had a 4 year old child. Imagine that that child was screechingly uncomfortable in a certain situation. Would you say to that child 'Well, find a way to deal with it', or would you just take them elsewhere? Do you think the child would feel more anxious in scenario 1 or scenario 2?
As adults, we are deemed not to need our parents to be responsible for us anymore, not because we don't need someone else to be responsible for us, for our welfare, for our actions, but that doesn't mean that nobody is responsible for us anymore, because we take on the role ourselves. This includes, just like with that 4 year old child, making sure that we listen to and respond to the feelings. Just like that child, if we ignore our feelings and force ourselves to be in screechingly uncomfortable situations, we will feel anxious.
You haven't 'forgotten who you are'. In the instance you've mentioned, you are not someone who loves to eat out. That's one of the things that makes you you. Who you are is 'what you like and what you don't like'. You might like Rubiks cubes so much that you are a person who regularly attends Rubik conventions. You might like cooking so much that half your time is spent in the kitchen. You might hate horses, so, even though lots of your friends are riders, you don't go with them when they go to the stables. 'Who you are' is what you enjoy.
What do you enjoy? What do you hate? That's who you are. That's what you build your life around. And once you do that, your anxiety will diminish dramatically, because the 4 year old child in you will know that 'mummy' (i.e. the adult you) will look after them, will not put them in unpleasant situations, will not tolerate seeing them uncomfortable, etc.