I agree with Carleton. It is a tragic event inasmuch as any life-changing injury like that is tragic, and I feel very sorry for her in that sense, but she's absolutely developing the right attitude for coping with it. I'm reminded of Alex Zanardi, the former IndyCar and Formula 1 driver, who lost both legs in a racing accident then starting winning Paralympic titles in hand cycling; I suspect we haven't seen the last of Kristina in rainbow stripes.
I guess we all know, whenever we get on our bikes, that there's a potential for serious injury. Whether the track is safer or more risky than the road is ultimately a moot point; we know the risks and we accept them. Sometimes this happens. That doesn't make it any less sad, but I am confident that it's not the end for her.