The most difficult soft skill to teach my students is keeping their personal lives personal and their business lives business. I try to explain to them to be like a duck and let things roll off your back. When you leave home to go to work, let home issues roll off your back and stay there. When you leave work to go home, let work issues roll off your back and stay there. If you are able to keep these separated, it will make your life easier. I also give them the example that they wouldn't want me to stand in front of them and tell them all about my personal life when I am supposed to be teaching them a subject. So, they shouldn't do it to their co-workers/employees or customers.