vacillator

Example:He was a fluctuator, never remaining firm in his beliefs.

Definition:a person who varies or wavers in their opinions or actions; especially one who frequently changes, as between sides, doctrines, etc.

Example:She was a wavering character, unable to make up her mind.

Definition:tending to move to and fro; not steady or firm; shaky.

Example:He was undecided, vacillating between his two options.

Definition:not having made a decision or come to a decision; still in doubt about what to do or think.

Example:She was unsure, vacillating between her beliefs.

Definition:not fully confident or certain.

Example:He was unresolute, vacillating in his decision-making.

Definition:weak in will; irresolute; wavering; hesitant; weak-minded.