You can do several things as an instructor to comfort your students who feel restless in your course. 

Feedback from students is important to your own prfesional development.

Creating a professional relationship with your students shows them that you are still human and have a life outside of being an instructor to where it can make you not as intimidating to them. 

Frustrations can still arise in an online class through various forms and ways. 

Not only does professional development help you better yourself but it helps your students out as well since they are always going to be getting the best version of you, and a version of you that is always growing and developing as an instructor.  

Communication and feedback are very important. Having clear expectations and asking what is needed is also important.

It's very important to keep your work and personal life separate. Having good communication and responses on your students discussions boards and posts is very important.

Minimizing distractions and making the most of your online tools is key to your workload management. 

I will create lots of interactions for my students to be a part of like discussions and small groups. 

Always show everyone respect, and a consistent routine and breaking course material down can help other struggling with PTSD.