>Besides, my family (every member of
>it, practically) are about as different from me as I could imagine.  To me,
>mental similarity is more important than genetic similarity.
Well, there you have it.  I think most Extropians would agree with the second
statement, although many share mental similarities with their families (I
do).  Naturally your family isn't going to approve of this attitude.
I think it's valuable for happiness to have people you are very close to,
have been close to for a long time, and will be close to for a long time.
 Family is an easy and common way to get this, but it's not the only one.