He played one game in the 2009-2010 season, and returned in the middle of the 2010-2011 season. Then he was pushed into the boards by Zach Bogosian of the Jets:
Bouchard tried to come back, but hasn't been able to.
Now, he's not the centerpiece of our organization like your guy is, but he is a talented top-six forward. Given the length of his convalescence last time around, I for one am not expecting him to play until late in the 2012-13 season at the earliest. He may surprise me, but I'm not going to bank on anything right now.
I, like many people I talk to, are terrified when we do see him on the ice, for exactly what happened to him in Winnipeg. Bogosian wasn't trying to hurt Bouchard, at least that's what I have to assume (and, incidentally, what the NHL said), and I know many players respect their colleagues in the other jerseys (Alex Burrows excepted; pardon my frankness, but he's just a dick).
Your concerns are justified. But as we learned with Bouchard, the best you can do as a fan is to support your local superstar and hope for the best. Assuming his doctors are competent and have signed off on his return, he's going to be ok.
Bouchard took a lot of hard hits between when he came back and when he was hit by Bogosian. Many were up high. Had Bogosian not pushed him into the boards at such a weird angle, there's a good chance he'd still be fine.
So trust your instincts. Know that while yes, it can happen again, your guy is getting the best care he can. Now sit back, enjoy the ride, and good luck.