A common symptom of PTSD is called hypervigilance.

Hypervigilance is an enhanced state of sensory sensitivity accompanied by an exaggerated intensity of behaviors whose purpose is to detect threats. Hypervigilance is also accompanied by a state of increased anxiety which can cause exhaustion.

Sensitivity to touch could very well be your hypervigilance. I'm not a doctor, so I can't say that this is the cause, but it could be. I've had to work on mine, but I had gotten the same way.

Welcome to PC, though I'm sorry for your loss. Hopefully this site will help offer support, understanding and help you to feel less alone.