Can we all agree that Jotaro has ptsd?
It's either that or accept that people get old and with age their bodies become slower and stiffer and takes much longer to regenerate from wounds and stuff (unless you're a vampire or something), also people become lazy or comfortable with the situation...
To be fair Jolyne deserves this.
She flirted with the driver causing him to look away from the road and helped him hide the corpse, the plea is just the nail in the coffin.
Thankfully she has a stand to solve the situation.
I don't think that's the kind of thing that you just forget and pretend nothing happend.
Even if you forgive them it's not easy to just be friends like nothing happend.