A whipstock assembly has a whip, a packer, and an anchor. The packer connects between the whip and the anchor and sets after the anchor is set. The anchor can be set mechanically or hydraulically. To communicate hydraulic pressure to the hydraulically-set anchor, the packer can have an internal bypass for communicating fluid or for passing a hydraulic line from the whip to the anchor. The packer is set mechanically with set down weight applied from the whip via a setting tool or the like. The packer sets eccentrically in the casing and acts as a fulcrum to push the tip of the whip against the inside of the casing.