However he also recalls a pious tale of the chaste women who, in danger of being raped, chose to jump into a river and drown, rather than suffer that injustice against chastity. They are regarded as saints.

This is an example of the double effect where someone does not deliberately intend to kill herself but in order to prevent an even greater evil (her involuntary cooperation in another's sin) that would be the forseeable result of her jumping into the river.

Their intent is to prevent sin , however. Their intent is not to self destruct. The self destruction is not a result of despair in relation to GOD's Commandments but rather a response to obey them and to prevent Their neighbors sin as well. In that regard it is not ѕυιcιdє born of despair.  Just like when a soldier jumps on a grenade to save his Buddies in War.   If no buddies were around and he jumped on the same grenade out of despair - the result is the same but the underlying moral causation is not

Judas was depressed and in despair. He was also very remorseful of what he did. But instead of asking for forgiveness, he offed himself. Now, we are quite certain that Judas is in Hell.

From the testimony of Gloria Polo about ѕυιcιdє;

While I was crying out, I began to hear crying thousands and thousands of persons, youth… Yes, above all youth, with so much suffering! I perceived that there, in that horrible place, in that quagmire of hate and of suffering, they were gnashing their teeth, with screams and laments that filled me with compassion and that I will never be able to forget… (Already 10 years have passed, but I still cry and suffer, when I remember the suffering of all those persons)… I was saying, I understood that in that place there were those persons who, in one moment of desperation, they committed ѕυιcιdє… Now they are in those torments, with those horrible beings near them, surrounded by demons that torment them. But the cruelest of these torments was the absence of God, because there one does not feel God. I understood that, those who in one moment of desperation took their lives, had to remain there, within those torments, until all the time that they might have spent on the earth had passed: because all those who kill themselves, go out of the Divine Order.

Those poor persons, above all so many youth, many, many… They cry and suffer much… If man might know the suffering that awaits him, never would anyone make the decision to take his life!

Do you know what the greatest torment is, there?
It is to see how one’s own parents, or relatives, who are alive, are crying and suffering with a tremendous sense of guilt: if I would have punished, or if I would not have punished, if I had said to him, or if I had not said to him, if I had done this or that… In the end, these regrets so terrible, - a true hell for those who love them and remain in this life - , they are what makes them suffer the most. It is the greatest torment for them, and it is here that the demons rage, showing these scenes:

“Look how your mother cries, look how she suffers, look how your father suffers, look how they are desperate, how they are distressed, how they blame themselves and discuss, accusing each other reciprocally, look at all the suffering that you caused them. Look how they rebel against God. Look at your family… All this because of your fault!”

That which these poor souls need, is that those who remain down here might begin a walk of conversion, that they might change their life, that they might do works of charity, that they might visit the sick… And that they might offer Masses in suffrage for the soul of the dead. These souls benefit enormously from all of this. In fact, the souls who find themselves in Purgatory can no longer do anything for themselves. Nothing! But God yes, through the Mass. Also we must help them in this way.

http://testimony-polo.blogspot.com/

Maybe they might be in purgatory.  

We have to pray for their souls no matter what.

A human being who dies as result of ѕυιcιdє, has committed murder against self, which is to say has died in mortal sin, (against fifth commandment and of despair, against the Holy Ghost) and thus has damned his soul to eternity.

This requires a judgment of fact. If he had the full use of reason, yes. If not, I don't know that you can make that judgment and you may want to take a look at the canonical penaties for ѕυιcιdє and attempted ѕυιcιdє.