WordNet sense 1 (have recourse to):

recur, resort, resort

WordNet sense 2 (hang (back) or fall (behind) in movement, progress, development, etc.):

dawdle, lag, fall behind

WordNet sense 3 (move back and away from):

recede, retire

WordNet sense 4 (retreat):

lose, drop off

WordNet sense 5 (go back to bad behavior):

lapse, regress, relapse, retrogress, recidivate, regress, relapse