So often people believe they have to try and make their friend feel better. They have to make them happy again. What they don't know is that the easiest option of how to help is the only one that usually makes a difference. All you have to do is sit with your friend and acknowledge that yes, this is truly awful and that you are there for them. Avoid "at least" at all costs. These two words are so incredibly damaging. When you use them you are basically telling your friend that they should not feel the way they do.
Allow your friend to speak their heart. Let them cry and be angry. Don't change the subject. Let them be the one to do that. Be honest with them, if you don’t know what to say, just tell them that. Let them know that you are there for them and that you are sorry that you do not have the words to make things better. Your honesty is appreciated.
If you can sit in the dark with your friend and just listen to them without judging them or making them feel like they should be happy because of whatever reason, then you are a wonderful friend. Just wrap your arms around them and give them a hug.
Be patient and forgiving. Your friend is in the darkest of places and unless you have been there yourself, you cannot comprehend what they are enduring. Don't wait for the old friend to come back. They are long gone. Your friend is a different person now and that is not a bad thing - it is just a different thing. They must learn how to live again and that takes time.
I hope I have made some sort of sense here. My mind is a little fuzzy since it is 2am but this is what is on my heart at the moment and I felt drawn to share this tonight.