left behind / blown past

I can't decide whether I've been left behind by the university system, or if I've just blown past it...

See, I had to take two years off on medical leave...lots of things happened during that time, to make it short I feel like I aged about a decade in those two years. Now getting back into school is such a hassle I feel like pulling out my hair half the time and collapsing into tears the other half.

All these happy, shining new faces...joggers breezing by on winged sneakers, tanned girls in tank tops, giggling...everyone I know who's left this uni hoping to come back has been an addict...and I am, too, but...I had such promise once, some ambition. Of course I still have the promise, I still have my genius brain, but I don't have any ambition now, nor any fear...