Over protected...

My husband is really worried about me getting stressed out at ALL during my pregnancy. He is having some health issues (nothing major just little stuff he's dealing with) and we found out today his dad was diagnosed with vascular dementia, which is basically a quick developing Alzheimer's. His parents live four hours from us so he cant be there to help and he really struggles with guilt for that. Hes really shook up and really trying to pretend to just be "OK" but he almost broke down earlier and now won't say anything other than that he's "fine". He doesn't get that the more he tries to protect me, the more stressed I feel. I don't know how to help him.