Hmm,
I could be wrong but that instructor sounds like a very experienced pilot but not a very experienced instructor, or one who is very stuck in his ways. Some pilots just aren't cut out for teaching. A good teacher in any discipline will be able to try different approaches to impart the required knowledge and skills thus adapting to different learning styles. Flying itself is very easy; integrating it with procedures, radio work and checklists is what makes it challenging and that's especially true in IFR work. It sounds like you just need more regular exposure to the environment so you can get comfortable and less intimidated.