Ah froggie, I feel for you. Commisserations on the loss of your dear grandpa.
You may or may not be right about the emotional connection, do you think you could find someone to talk to about it all.
Three weeks is a long time not to keep food down, I would suggest seeing the doctor but you have done that.
You could also try fasting 24hours, to give your gut a rest. Keep drinking pure water though.
On the other hand, if meat is ok, then maybe a good meat broth would also be ok.