get off the track

depart diverge wander

digress divagate ramble sin

circumlocute do wrong excurse get off the subject get sidetracked go off on a tangent

stay

be direct

go direct remain

ramble stray veer

babble depart deviate divagate diverge err rave shift swerve

get sidetracked go astray go off on a tangent lose one's way lose train of thought talk nonsense

go direct stay