Well, you better start worrying because it is definitely a problem. Go to Snopes.com and ask that question. People are being sued right now for using someone else's email.
Oh! And it's not the "Net" police that's going to be knocking on your door!
Sorry my friend,not too worried when I haven't done anything wrong!!
I have more serious things to be "worried" about in this life..
Hey,it's the internet,please don't take it so serious!!
And if your talking about that husband looking at his wifes mail on a shared computer,I think that the lawyers will sort that out..
BTW,Snopes is not the the be-all end-all that it's claimed to be..