The problem of reacting in anger has always existed and the consequences are readily apparent. Learned impulse control and self monitoring as one matures seems to work easily enough unless you have some really deep seated emotional issues that need to be dealt with professionally. But this issue of experiencing unbearable feelings of loneliness whenever you have a free moment is very foreign to me. It seems a very low level of emotional maturity. Even babies can amuse themselves in a crib. No telling what they are thinking, but they seem to just be enjoying what they are experiencing (to a point, of course). No doubt there are others babies.. and adults.. who need constant attention. Therein lies the problem.
This is not to say that humans don’t need emotional and social connection, but that need can exist along with the actual appreciation of being alone. It’s a balance that perhaps is becoming in short supply. But seriously folks, you can learn to do this.
Re C.K.’s explanation of the positive feeling after crying, I believe it comes because you have released tension. No doubt endorphins are also involved.