Not forgiven in the next world… If you are not forgiven in the next world, I think it is referring to a realm worse than purgatory. Through purgatory you theoretically gain forgiveness, if you are not forgiven you go to hell.
Despite all the links and explanations you have been provided…seems you still misunderstand or still carry your ingrained belief about purgatory…
There is no forgiveness in purgatory…is for purging of our sinful nature.
To enter purgatory, one must have been forgiven or asked for forgiveness already.
catholiceducation.org/articles/apologetics/ap0091.html
Purgatory: Holy Fire
SCOTT HAHN
Those people who in God’s grace and mercy are allowed to enter into purgatory die in a state of grace, not just with supernatural faith and hope but with supernatural charity that was alive in their hearts and lives. That is the prerequisite for entering purgatory. You cannot die in the state of mortal sin; you cannot die estranged from God, in a way hostile to God, having committed yourself to valuing things of the world more than the creator of the world. You cannot do those things and enter purgatory, much less heaven. Purgatory is not a second chance. It’s only for those whom God has from all eternity destined for heaven, and it’s only for those who die in a state of grace.
Furthermore, we’ve got to clarify the fact that it is not to make up for Christ’s unfinished work. I’ve already said that, but that, too, is a common misconception that continually needs clarification. There’s nothing inadequate about the work of Christ. It’s finished, but it needs to be applied.
Earthly goods are good, but they are only hors d’oeuvres. They are only meant to whet our appetite for the heavenly banquet. If we pig out on the hors d’oeuvres, what’s going to happen? We’re going to lose any desire for heaven and the banquet of the lamb. So the Holy Spirit in love sends fire and ordeals which come upon us to prove us. To prove you as though something strange will happen to you, but rejoice insofar as you share Christ’s sufferings “…that you may also rejoice and be glad when His glory is revealed.”
He brings one fiery ordeal after another. If you are suffering a great deal. If you are going through a kind of purgatory on earth, you rejoice. Those who are fat and lazy and have it easy, they should beware. As Mother Teresa continues to say, “These are God’s tender caresses, this suffering.” The more suffering that you endure in faith and hope and charity, the more God’s love is being revealed to you. No wonder the gospel will never sell in the world. There is no way to teach this so that Madison Avenue PR men and women can just go out and make this popular without perverting it and watering it down.
This is why purgatory is so hard for us to understand. We don’t want to carry the cross. We want to make an optional clause in our contract with Christ. “If you want to be my disciple, you’ve got to carry the cross. You’ve got to die to self.”