I no longer have a period and havent had in years but i've always ahad a brownish stain in the crotch of my panties and it wont wash out. what is it?

"Brown and out": I don't know what the brown stain is without seeing it, and I am therefore "out" of answers. You also do not mention your age- post menopausal? Even if you are post menopausal, the brown stain could be blood, so go see a GYN MD soon as endometrial or cervical cancer presents in this way.

Investigate: A persistent brownish stain in a women of an age, where she no longer has her period, should be investigated by a gynecologist. It could point towards a precancerous condition of the uterus.