I think the attitude of others depends a lot on their experiences with PTSD. If they have worked with PTSD suffers for a long period, they tend to understand better.
An incident occurred to me that might illustrate this point. I was having a series of flashbacks and acting irrational so my family called an ambulance to take me to the hospital. One of the ambulance attendance (technically the paramedic) was totally afraid of me. The other one (the driver) was very understanding and supportive. The driver had friends with PTSD and understood the problem. (BTW this incident occurred because the doc I was seeing at the time put me on a med that I reacted badly to.)