hi tanpopo what I would suggest if you decide to leave you're sensei is to let him know, instead of just not coming back, remember he got you to where you are today and has installed the building blocks for you're karate training-if you let him know how you feel, it may be just what is needed for youre sensei to take notice of what is happening, if all else fails at least you showed respect in telling your sensei face face. Let me know how you get on. Den