If you're following the Companions questline, it's mandatory in order to continue (at least as far as I know), and you will have the opportunity to cure yourself if you so desire by the end of the questline.
If you're following the Companions questline, it's mandatory in order to continue (at least as far as I know), and you will have the opportunity to cure yourself if you so desire by the end of the questline.
Good job on posting a spoiler for everyone who hasn't played any of the Companions questline in the General section of the forum.