Parents want so much to protect their kids, when it's often better to share real intensity of life with them. Why do people feel they "must be supportive" by denial and reasonableness when dealing with grief? Said from my own experience, it's possible that your teen has quite a bit more capacity for self-knowledge & the ability to be the one to comfort you than you might imagine as their parent.
I'll tell you about myself. I wouldn't have been the person I grew to be if my parents hadn't died when they did. I would have never known my mom before she died if my dad had not died. For that reason, (and the fact they died exactly 5 years apart) I came to consider it totally fitting that my dad died when he did - when I was eleven. There was no grief counseling my my era.
Grief was a strange gift for me. Because the experience of grief was so real, grieving made me realize how deep my feelings really were. It made me realize my priorities and what my values really were when I had no clue what values even were. I realized how the people who were in my life were important to me. Now I knew exactly how I was going to express what I felt about them while they were alive and sharing time with me now. I was no longer upset about things that really did not matter compared to the requirements of having a real reason to be grieving. I got skilled at uncovering what we have to offer each other now in the time we have. I realized every time friends part, it may be the last time you see each other alive ever again.
My teen friends seemed like indulged kitty-cat pets - I say that with ultimate affection for them. They had never had to confront anything as intense as grief or being physically damaged for life yet. I had to understand that they were scared of me, as if I had a disease - that's why they isolated me...and that was OK. I gained compassion for their fears.
I ran and biked in secret, among other things I did to draw out my feelings. They became delicious, precious, sacred secrets...sources for art. I cannot say I'm "glad" to have experienced grief when I did, but it made me who I am today. My only regret is that from the pain of remembering, I obliterated too many of the happy memories of my dad because the grief was too sharp.
After I'd prayed for years for my grief to end, my disillusionment and denial was answered by an intensity of a consciousness awareness gift that hit me blind-sided. I know now that gift would never have happened had the grief not been there - so for that reason, I am strangely thankful things happened the way they did. My experience of death made my life into a "real life."