First talk to your friend. The longer you let this fester the worse it will get. Second talk to your Sensei privately and see what he reccomends you do as regards to the Dojo.
As for not training because you lost control I would suggest you train yourself to keep control. I have had a similar experience and I would wager everyone else on this forum has as well. Don't let it rob you of the joy of practicing the art. This is just one little setback on the road of life you have to keep traveling.
Hope this helps.