When we feel grief, we feel as if the whole world is crashing down around us, that the darkness and shadows is everywhere; we feel that a part of ourselves had died with the person we lost, that the one we lost took a bit of us so they won't forget the person they left behind.
We've all felt grief at one point of our lives, but sadly some aren't able to let go of the grief; grief then sometimes leads to anger, which leads to revenge, which leads to self-destruction, which leads to loss, then finally the cycle starts again.
The cycle will never end unless the person in grief is strong enough to break the cycle, and let go, with grief you feel a pain that will never go away; regret and grief can sometimes connect because we feel regret when we grieve because we did or said something to the one we lost, or we never told the person how we feel about because we were too scarred to let it out.
We also question everything and everyone around us, and our mortality; and when we loose someone to suicide, we wonder why we didn't listen to their cries for help or pay attention to the warning signs?
You feel broken beyond repair and that you'll never get over the pain, you'll also feel defensive because some don't understand what you're going through, they couldn't possibly understand what you're going through.
But if you're strong enough, you can pull through the grief and move forward; even though it hurts to.