why suffer?

Received a bad news during lunchbreak. My friend's sister passed away from leukemia.
It's really sudden and shocking as the sister is only in her late twenties..
Really din know how to comfort her as i've never encounter such a great and painful suffering.

In 2 Corinthians 1:3-6, it's stated clearly why we suffer...
Blessed be the God and Father of our Lord Jesus Christ, the Father of mercies and God of all comfort, who comforts us in all our affliction, so that we may be able to comfort those who are in any affliction, with the comfort with which we ourselves are comforted by God. For as we share abundantly in Christ's sufferings, so through Christ we share abundantly in comfort too. If we are afflicted, it is for your comfort and salvation; and if we are comforted, it is for your comfort, which you experience when you patiently endure the same sufferings we suffer.
-- to comfort others who will be in the same afflictions that we now are in --

Mark 13: 2-5,
Jesus answered: 'Do you think that these Galileans were worse sinners than all the other Galileans because they suffered this way? I tell you, no! But unless you repent, you too will all perish. Or those eighteen who died when the tower in Siloam fell on them - do you think they were more guilty than all the others living in Jerusalem? I tell you, no! But unless you repent, you too will all perish.'
-- sufferings are to warn each and everyone to repent OR perish --

SC, be strong! May God of all comfort and mercies comfort you and your family.