I wouldn't consider yourself selfish by not having a child. Bringing in a child into this world is simply contributing to society, but then you can do that in many other selfless ways. But I feel there will be a personal sacrifice by not having a child. I consider myself a loner beside loving my wife, I have no reason to leave a legacy. However, there is something to be said to share your life, experiences and knowledge with someone who can benefit. Passing that to someone is rewarding for sure i.e. Big Brothers, bt there is something more, something special if it is your own flesh and blood. Something very innate.
Lastly, typically you and your spouse will most likely die separately. Even with families close by, there is nothing like knowing your own flesh and blood will be there. The inherent trust and bond is undeniable.
>>Lastly, you absolutely will LOSE your previous life. There isn't a part of it you can retain. It's gone....period.
Little overly stated since my son needs me 24/7 now. However, overtime, he'll need this space and my wife and I may be able to get back to where we were. Of course one factor to consider is age so this is where having your child at an earlier age has it's advantages. So truly get back to where we were will most likely be based on your age.