Of course, I remember you. First time we spoke I told you about your name, that it has special qualities to it that you have also and that it wasn't by accident you were given that name.
You may try counting your pulse before and after eating wheat. If it goes up afterwards, there may still be an intolerance or allergy. Oftentimes, the reaction is whatever else there is in the wheat, and nowadays there is a lot of it stuff in it that doesn't belong there.
Your sister is jealous of you for certain qualities you possess and she doesn't. She is unhappy wihtin herself. So when she says she doesn't care if she offends you, she basically means she does care. It offends her (bothers her) that she cannot be like you. She manipulates others because she is uanble to love and appreciate herself, so she resorts to external sources of comfort, power and control. It is all fear and guilt-based. Tell her that you love her anyway (if you can) when she tries to offend you. She can only offend you if you are offendable. If you don't take her offence personal (which it is not) it will pass right through you. Once she realises she cannot hurt you anymore, seh will stop trying. And even if she did, it won't work. Look at the space between her eyebrows when she is like that, and you may sense the low self worth and fear behind her words. If your brother lets her manipulate him, it is his problem rally, and reflects a weakness in him that she helps to trigger.