2 Corinthians 1:3-11
Blessed be the God and Father of our Lord Jesus Christ, the Father of compassion and God of all encouragement, who encourages us in our every affliction, so that we may be able to encourage those who are in any affliction with the encouragement with which we ourselves are encouraged by God. For as Christ’s sufferings overflow to us, so through Christ does our encouragement also overflow.
If we are afflicted, it is for your encouragement and salvation; if we are encouraged, it is for your encouragement, which enables you to endure the same sufferings that we suffer. Our hope for you is firm, for we know that as you share in the sufferings, you also share in the encouragement.
We do not want you to be unaware, brothers, of the affliction that came to us in the province of Asia; we were utterly weighed down beyond our strength, so that we despaired even of life. Indeed, we had accepted within ourselves the sentence of death, that we might trust not in ourselves but in God who raises the dead. He rescued us from such great danger of death, and he will continue to rescue us; in him we have put our hope (that) he will also rescue us again, as you help us with prayer, so that thanks may be given by many on our behalf for the gift granted us through the prayers of many. 2 Cor 1:3-11

ENCOURAGEMENT
Suffering creates a need for encouragement. God offers the encouragement. Our need causes us to accept encouragement from God, thus growing closer to God. Further, we become better able to comfort each other.

Blessed be the God and Father of our Lord Jesus Christ, the Father of compassion and God of all encouragement, who encourages us in our every affliction, so that we may be able to encourage those who are in any affliction with the encouragement with which we ourselves are encouraged by God. For as Christ’s sufferings overflow to us, so through Christ does our encouragement also overflow. 2 Cor 1:3-5

EMPATHY
Your suffering creates an opportunity for my empathy, and thus an increase in my ability to love. My suffering creates an opportunity for your empathy, and thus an increase in your ability to love.

If we are afflicted, it is for your encouragement and salvation; if we are encouraged, it is for your encouragement, which enables you to endure the same sufferings that we suffer.
2 Cor 1:6

HOPE
After watching others live through suffering and encouragement, we have reason to hope.

Our hope for you is firm, for we know that as you share in the sufferings, you also share in the encouragement. 2 Cor 1:7

TRUST
Hope fulfilled increases our ability and willingness to trust.

We do not want you to be unaware, brothers, of the affliction that came to us in the province of Asia; we were utterly weighed down beyond our strength, so that we despaired even of life. Indeed, we had accepted within ourselves the sentence of death, that we might trust not in ourselves but in God who raises the dead. 2 Cor 1:8-9

HOPE (again)
After living through suffering and encouragement ourselves, we have strong reason to hope.

He rescued us from such great danger of death, and he will continue to rescue us; in him we have put our hope (that) he will also rescue us again, 2 Cor 1:10

GRATITUDE
Human love often grows out of gratitude.

as you help us with prayer, so that thanks may be given by many on our behalf for the gift granted us through the prayers of many. 2 Cor 1:11

Encouragement, empathy, hope, trust, and gratitude are all essential components of our ability to love. Our ability to love is essential to our salvation. Our salvation is essential to our ultimate, true happiness. Thus, suffering is essential to our ultimate, true, eternal happiness.