Go over there and get your stuff back. It is your stuff get it back. Don't do passive aggressive. Just get your stuff. Be polite about it, and get your stuff. Say what you wanna say. You'll feel better when you have your things back. You really shouldn't have gifted them and then asked for them back. But that isn't the point here. Tell her you know she has some fabric of yours and you need it back.
Being passive aggressive, and doing nothing for yourself will hurt worse than actually calling the bluff, and getting what is rightfully yours.
Don't let family members manipulate (in their own little way) and make a fool of you. These kinds of petty skirmishes are to be dealt with head-on.
It's easy,
that's my stuff and I want it.
Say...Oh Hai...I just dropped by to get my material back. There is no question that she has it. And there is no question that she will give it to you. BE THE ADULT.
