Based on your description, the cause is more likely sudden bloating (water retention), or perhaps an allergic reaction (to your laundry detergent, or whatever).

The reason I say that is because your problem seems to be intermittent (few days), long-term (8 mo), and in areas that are particularly constricted (bra, waist/thigh area). Also, although some of us would relate to having some sort of problem in this regard, the sensations you describe ("itchiness", "tingling", undefined "hurt") are not how most of us would describe our "clothing" issues.

The neurological "itchiness" that one gets from MS is concentrated to one or many very small and defined spot(s), not a large area or large patch of skin. It would be like a mosquito bite itch, with nothing visible, and it is very distinct/describable. The skin "hurt" feeling is not usually concentrated to areas such as the "bra line" or "waist area" either.

Additionally, MS clothing 'weirdness' generally comes accompanied by other specific 'MS-weirdness' that you don't currently have.

Cherie