If that were true - there would be no point in escaping it. No point in indulgences.
You leave out "so much"
Augustine (De Civ. Dei, lib. XXI, cap.xiii and xvi) declares that the punishment of purgatory is temporary and will cease, at least with the Last Judgment... Augustine in Ps. 37 n. 3, speaks of the pain which purgatorial fire causes as more severe than anything a man can suffer in this life, "gravior erit ignis quam quidquid potest homo pati in hac vita" (P. L., col. 397). Gregory the Great speaks of those who after this life "will expiate their faults by purgatorial flames," and he adds "'that the pain be more intolerable than any one can suffer in this life" (Ps. 3 poenit., n. 1). Following in the footsteps of Gregory , St. Thomas teaches (IV, dist. xxi, q. i, a.1) that besides the separation of the soul from the sight of God , there is the other punishment from fire. "Una poena damni, in quantum scilicet retardantur a divina visione; alia sensus secundum quod ab igne punientur", and St. Bonaventure not only agrees with St. Thomas but adds (IV, dist. xx, p.1, a.1, q. ii) that this punishment by fire is more severe than any punishment which comes to men in this life; "Gravior est omni temporali poena. quam modo sustinet anima carni conjuncta".
The Catechism states
1031: "The Church formulated her doctrine of faith on Purgatory especially at the Councils of Florence and Trent"
Council of Florence (1438-1443):
"If they have died repentant for their sins and having love of God, but have not made satisfaction for things they have done or omitted by fruits worthy of penance, then their souls, after death, are cleansed by the punishment of Purgatory...the suffrages of the faithful still living are efficacious in bringing them relief from such punishment, namely the Sacrifice of the Mass, prayers and almsgiving and other works of piety which, in accordance with
the designation of the Church, are customarily offered by the faithful for each other." 12