I found this interesting article in the Sales and Marketing Coach website. It provides tips to cope up with Negative emotions.
"As we all know, sometimes language breaks down, and communication grinds to a halt. This can leave the owner feeling irritable, angry, frustrated… and with a desire to vent to his/her employees or staff. While there may be instances that such sharing would be appropriate or helpful, there are many instances where this is not the case, and venting anyway may result in a significant loss of credibility and respect from key employees and contacts."
It may not be easy to follow all these. But as he says "Regular use of these tips will help you stay well balanced & happy as your business grows and flourishes.", it will definetely help.