To the op -
This is in no way your fault.
I can be sure that the person doing it didn’t even think of your truck as anything other than a vehicle. They wouldn’t have thought of how it affected you.
People are right in that any logical thinking person would see that there is obviously going to be a driver who would be affected.
Trouble is, for whatever reason, they aren’t being logical or rational.
Your truck was just a means to an end. Unfortunately literally.
I can (and this I can voice from experience) say that the family will be probably confused and clutching at any straws they can to try and understand why.
You can’t answer that for them but you know deep down there is nothing you could have done to prevent it. You are not a mind reader.
This sounds flippant but unfortunately it’s accurate - you were unlucky to have got caught up in someone else’s mess. Nothing more. Nothing less.
One other thing - talk to someone. Anyone.
I consider myself quite mentally resilient. In a previous career I could always distance myself or switch off to it.
I thought I could do the same when it was closer to home. I had to be there for everyone else.
Took two months but in the end I cracked a little. Huge panic attack and sort of lost it.
I was forced by my family to get help.
No - not an asylum! I just spoke to a councillor a few times. Someone who is not tied into it all. The little bit of distance gives them a good viewpoint. Rightly or wrongly - friends and family often just say what you want to hear.
Looking back - I obviously felt awful anyway - I shouldn’t have and didn’t need to put myself through anymore stress. I should have nipped it in the bud.