I am sure she is just stressed. It also sounds like she wants control of the all the planning (which is what she does in her everyday life). From what I am realizing a lot of brides to be have a hard time letting go of the reins. I would just talk to her when she has calmed down and just let her know you are only trying to help, but if she doesn't need or want it, you will do what you can to respect that. I am sure she wants and appreciates your help, but she wants the control. So, next time you do research, etc... just let her know what you found, so she can be the 1st person to relay it to your guests. Good luck!!!