Re: Cold Sensei
I wonder.. could this sensei be romantically interested in you? Maybe the distancing is due to a misunderstanding / hurt feelings.
But.. all the others have good advice as well. If talking in the open about it dosen't help then just practice and try to find other friends to fill you social needs. Eventually something may be said, solve itself or in other ways become apparent. Until then - just focus on being a nice person, enjoy friends and train hard and in joyful spirit.
PS: No.. I've never experienced anything like this.And I hope none of my students have.