There is no substitute for experience. You may think you understand another’s grief, but until you experience the death of one you hold dear, you cannot fully understand how another suffers. You may think you know what pain is, but until you suffer yourself, you do not fully understand. As a spirit, all is love and light. As an earthly being (for just a while a role you play, mind you), you have the opportunity to experience pain as well as full health; grief as well as celebration and joy.
Yes, your life has its share of ups and downs. That is why you are here—for the experience. Do not wallow in the grief and pain. Experience it. Learn from it. Acknowledge it, and then rise above. Once you have pulled yourself up, now you can do the same for others. All others are here for the same reason: to experience duality and grow from it.
Rejoice! You are alive!