Marriane my DH was always told by his mother (both now deceased) that he was a 'weekend's leave from the Army' (WWII) and was never planned as they already had three other children and didn't want anymore. While he tried to brush it aside, I know deep down he was hurt, so I can understand why you feel this way. 
My own biological mother was unmarried when I was born so it appears an inter-family adoption was arranged with help from the catholic church and I was raised by her brother and his wife. Unfortunately this brother abused me in every way possible and even as a small child I could never do anything right and was never shown any love in that family.
On the other hand, my bio Mum (known as Aunt) showered me with love and affection and I remember many, many arguments between her and her brother which were always about me. In my late teens she would always say 'you and I need to have a long talk some day' but it never happened and when she said these words she would become visibly upset and start shaking....she never married and I don't have any indication who my bio father could possibly be, although I do think I may have met him at her house a few times when I was very young. At weekends my adoptive father would take me to visit her and I distinctly remember this tall, dark haired man (often in uniform) would be there and they would play games with me, but he would arrive 'after' and leave 'before' adoptive father would come to collect me and one of the games we played was 'our little secret' where I was told not to mention this man to anyone. I think I was approx 4 yrs old and would love to remember the colour of his uniform or his name (or what I used to call him), but he too, showered me with love and would bring gifts which were always left at 'Aunts' house, not to be taken home.
A few years later I clearly remember one weekend she was constantly crying and used one of her beautiful, lace hankerchiefs to mop up the tears and took me to the local wharf where she was shaking uncontrollably when she held my hand while crossing the road or walking close to cars. So I can only assume the tall man had died or left or ??? She desperately tried to keep her grief hidden, but even though I was very young, I still 'knew' something horrible had happened.
She would take me on the ferry, introduce me to her friends and tell them I was a 'delightful child'...if only that sentiment was shared by her abusive brother and his wife. Anyway, I knew she loved me unconditionally even if we never got to have the 'long talk'... which still makes me sad.
By strange coincidence, my adoptive parents would 'never' use the word 'adopted' or talk about adoption in any shape or form and if I dared say the word I would get (yet another) beating so you soon learn to be selective in your words etc as the punishment is too painful (physically).