It is with sincere regret that I am obliged to tender my resignation from the membership of ____________ (Club Name), on account of my failing health. Of late, I find it well nigh impossible to continue as an active member of this prestigious club that I love so much. I am to offer my resignation with immediate effect.
Please be assured of my appreciation for such a long club-life I have enjoyed. Convey my appreciation and best wishes to all the worthy members of the club and the Board of the Directors.
With kindest regards.