People only try to contact you all the time & expect you to be available if you give them that expectation. Tell your coworkers that you're not going to be checking email on weekends. Tell your friends that you don't answer your phone after X:00pm. Or just don't answer it. The calls will stop.

Almost everything can wait a couple hours, or until the next day. Personally, I don't like being perpetually connected. Often I'll go for a long jog, or bike ride, strangely happy about the fact that no one can contact me for the next hour or two, even if they wanted.

Set your boundaries, or they will be set for you.