Spondylolysis...is recovery normally this hard?

Ok so I need a no B.S assessment. I've tried the advice of doctors and therapists alike without satisfaction, and now i turn to the public. My condition involves spondylolysis, a fracture of the lumbar spine. Now in my particular case a recent MRI shows that the condition had healed from a previous MRI 6 months before (followed by rest/brace/recovery) and the problem was corrected. Now i know that just because the MRI cleared the condition it didnt necessarily mean I was pain free, I had to work my muscles back into shape in order to continue sports. But here is where the problem lies, I've been exercising and performing PT workouts for the past 3 months and at times I still feel the sharp grueling pain from spondylolysis. My doctor told me I might have these back aches for some time but considering I'm young (17), shouldn't my body have been able to heal by now. Certain movements cause pain during exercise (such as arching the spine) while others are pain free. I desperately need some help here. Please anyone who has similar stories, or success with this problem feel free to "spill your guts" so to speak and tell me everything. Why does recovery feel this way?