I have an 8 yr old and for whatever reason have been unable to concieve a second child which i think most of the time I have accepted. However whenever I hear one of friends/relatives is expecting I always have that dragging feeling of when will it be my turn 
Even to the point where my lovely sister in law who has been trying for over 10yrs recently told me she was expecting and although I am genuinely happy for her I still have that same old feeling and if anyone deserves it it's her, I just feel like such a bad person.
Do you ever accept that you will only have one and you want more or will I always feel this way.