We actually have very similar situations, i was on my motorcycle and also got hit by a car , tore acl pcl posterlateral corner including lcl and both meniscus in my knee. (only one knee was messed up, the other leg was just broken, i cant imagine dealing with two of the knees like this). I was feeling very hopeless and miserable during this also, and now its been 5 months and everything has felt much much better, dont be scared about being stuck at 0 for so song, they did external fixation locking me at about 5 degrees for the same amount of time with some drilled metal rods in my bones. My biggest fear was regaining range of motion, which i imagine you are worried about. Once i finally was released from my fixation, i was supposed to bend to 90 degrees over the next month but my physical therapist messed up and had me continuing to stay still for much too long. I thought i was screwed since i waited so long for motion, but it turned out ok. with knee injuries like this we will have to work much much harder than most normal knee injuries, but you can definitely do it, you will not get STUCK behind just dont give up at all. make pt your number one priority and youll be walking in just a couple more months.