"An it harm none" also includes yourself, your family, etc.
How this line is interpreted is purely up to the individual Wiccan.
In my own case, I choose to interpret it to mean, "So long as no humans are deliberately harmed, do as you please." By harm, I refer to physical, mental, and economic harm; I am uninterested in emotional harm or other, less-defined forms of 'harm'. I also choose to interpret this as not causing needless harm to other living things, meaning no sport-hunting, casual abortions, child abuse, etc. No chopping forests down just to get a better view. No smoking around other people.
There really is no single, hard, fast answer to the question, Larsen.
Death is merely part of the cycle of life. Things must die so other things can live. Things die casually all the time in nature. Some harm always happens, but between humans, this need not be so.
In the broadest sense, the Rede is simply a suggestion or guideline for how to behave: when faced with a choice, determine whether any of your options will cause needless harm, and proceed from there. But it is not a Law, and many Pagans don't follow it at all.
There is also, for some Wiccans, a longer form of the Rede (Doreen Valiente's comes to mind, which is a lengthy poem full of odd concepts) that includes something along the lines of 'except in self defense, an it harm none, do what thou wilt'. Other Wiccan traditions have their own moral guidelines built roughly on this idea, or on other similar ideas.
So, do you have the same problem with, "Do unto others as you would have others do unto you?" Really, most religions have some form of the Golden Rule/Wiccan Rede in them. The idea isn't to cause no harm at all to anything - that is an abomination to nature. The idea is to not cause needless harm - but to recognize that many things don't harm people at all, so why worry about them? Why shouldn't two same-sex lovers do what they want, as long as they aren't hurting other people? Why shouldn't you be allowed (if it is your wont to do so) to walk around stark naked as long as you aren't going to freeze to death or burn up?
I'll try to give more clear answers later.
