I don't believe that a person is or can be complete without having children
Then you are not, as an individual, a complete person ... I think you'll find the fault lies with yourself rather than anyone else.
I don't have kids and don't want kids ... thankfully neither does my partner of the past more than a decade - as she once said "... what are they for?!"
I'm perfectly happy in myself and don't feel any kind of need for validation through offspring; and if you had children just so you could feel complete ... isn't that a little unfair on your kids? More than just a little selfish on your part?