Sometimes i slack on my pt exercises for chondromalacia. it leads to a bad flare and takes longer to strengthen. what damage am i doing? how bad?

Hard to say: The severity of the chondromalacia can only be determined with an MRI or surgery. However, at your age, it's unlikely that your damage is moderate or severe. Flares of pain can mean inflammation, and not necessarily damage. You are obviously learning the importance of sticking with your rehab. A brace can help as well. If I can help, then join my care team at www.healthtap.com/dr-clarkeholmes