I'm sincerely sorry about your friend and all you have been through. Would you change it? As in, do you feel that you acted admirably throughout your experience? If so, fuck it. Be proud of yourself and know that you do your best. Valuing yourself projects and results in others valuing you as well. Go to your reunion; the majority of those people have been through what you've been through and you have shared formative experience. You'll likely be pleasantly surprised. Wishing you the best. Cheers, b.