Listeners can easily tell if a violinist plays from the heart or out of techniques only. You must always remember that a violin is a very personal instrument. They say its one closest to your heart. You dont just play, you have to "feel" the piece/song. Try feeling the music. If its sad, you must interpret and "exaggerate" the highness and lowness and the dynamics. if its a happy piece, play it with a smile on your face, lighten up your mood. Sometimes, even without facial expression, people could feel the passion when you play from the heart. Even simplest piece can really sound very beautiful if its played out of the heart. I played Ave Maria, the simplest arrangement, and people had tears flowing from their eyes. you can too!!! YOU JUST HAVE TO FEEL THE SONG!!!

Now, interpretation is another different thing than playing with passion. When you try to interpret,you try to play a piece according to the composer's wishes. Observing the dynamic markings, even the ornaments can be very stressing. Usually, Bach is the hardest one in interpretation in my own opinion but I love Bach. Though strict, I find more freedom in his compositions. Going to the level of a 4year old kid, i might teach her that p is piano which means soft and f is forte which means loud then adding it up pp, ff, and so on and so forth until he can really distinguish and/or even the listeners can distinguish the highness and lowness of sound.

Seems like your instructor has such high expectations, which is a good thing though. Its hard giving out advices through forums like that the recipient could understand. I could answer your questions clearly but would still be a blur for you. Uhm, try at least, other violin instructors, talk to them personally or have them play it for you. That way, a visual experience would help.
I had a recent review about international violinists, of all the violinists, Asians, pariticularly a Filipino, had the best interpretation and had the fire of passion on his piece which the commentator said was burning within their hearts. I defy that, I really dont believe that Filipinos alone could have the passion in playing, maybe when you get to the stage and so nervous, you would lose the feeling you need for the piece, i could say that ANYONE could have the passion in playing the violin or any other piece.