No. The angel guardian never forsakes a man entirely, but sometimes he leaves him in some particular, for instance by not preventing him from being subject to some trouble, or even from falling into sin, according to the ordering of Divine judgments, because neither man, nor anything at all, is entirely withdrawn from the providence of God, for inasmuch as a thing participates being, so far is it subject to the providence that extends over all being.
Angelus custos nunquam totaliter dimittit hominem, sed ad aliquid interdum eum dimittit; prout scilicet non impedit quin subdatur alicui tribulationi, vel etiam quin cadat in peccatum, secundum ordinem divinorum iudiciorum, quia nec homo, nec res aliqua, totaliter divinae providentiae subtrahitur, inquantum enim aliquid participat de esse, intantum subditur universali providentiae entium.
God indeed is said to forsake man, according to the ordering of His providence, but only inasmuch as He allows man to suffer some defect of punishment or of fault.
Sed intantum Deus, secundum ordinem suae providentiae, dicitur hominem derelinquere, inquantum permittit hominem pati aliquem defectum vel poenae vel culpae.