It sounds like you're depressed. Your worries don't sound rational at all, especially the feeling of inferiority. You ought to talk to your doctor. Certainly you should not make a life-altering decision like abortion when you are so plainly under the influence of negative feelings.
Lots of people have three or more kids, kids that are widely spaced, or three boys. Your situation is completely normal. There's a family in my church with four boys. Those boys are a handful, but they're delightful too. My own brother and sister (yes, twins) are eight years younger than I am. He's the long awaited boy, and she's the third girl. My parents are in their fifties now, seeing the twins off to college, and we have a wonderful family.
Remember that pregnancy only lasts nine months, and when its done, you can forget all about every negative feeling you had. My pregnancy with my daughter was physically miserable, but once she was here, I forgot all about it. Your feelings right now are a product of your hormones. You have no idea how you will feel about this baby when he or she comes. Youngest children are often a mother's favorite.
Please do not consider abortion anymore. If, once this baby gets here, you honestly feel that you can't raise him or her with love, then arrange for an adoption, but give the baby a chance to get you to love him or her. Whether or not this child is what you hope for, this child is a wonderful bundle of joy and potential that will make someone very happy, but if you abort this baby, no one will ever get that chance. God can provide the love you're looking for. He did it for me when I was suffering from post-partum depression. If you adopt out this baby, you'll have the comfort of knowing that somewhere your baby is happy. If you abort this baby, there's only going to be a void where the baby could have been. There's no comfort in a void, at least not until you acknowledge that it could have been filled with a life and ask God to forgive.
Please, talk to your doctor, talk to a counselor (I would recommend finding a Christian one because I have the most confidence in their understanding of life), and give the baby a chance. If adoption sounds like an option you'd like to consider, adoption agencies are on the first pages of the yellow pages, and they don't charge the biological parents of the baby anything. The adopting parents pay all the fees.
I am going to pass your story on to some friends of mine who will join me in praying that your spirits lift and that things get easier for you and that God will show you a way out of this difficult situation.
God will help you soon. Love and prayer,
J.
Updated
An answer from a friend who went through something similar:
Please, don't dwell on how you are feeling now. Have faith that this little guy (girl or boy) is God's sweet creation, and instead think of the love you felt for the others as you held them in your arms after birth. YOU WILL FEEL THE SAME WAY, AND BE SO ETERNALLY GRATEFUL, AFTER THIS BABY IS BORN.
Everything you worried about in your letter was the same for me. I have SEVEN girls, the last was born 8 years after the others, I worried about having so many kids, I was drowning after the first two and worried about having yet another, I never felt good during my pregnancies, I thought "what a disaster" becoming pregnant the last time. My parish priest encouraged me and talked about what joy this last baby would bring into our family.
Believe me, he was right, and the same will be for you. This baby will be such a source of happiness for you and the others in your family, you will be so grateful for this wonderful gift God gave to all of you. You will shake your head remembering that you thought he/she was "a mistake". Believe me, it all happened to me, and its true.
Hang in there, Kiddo, and you will be so very grateful that you did!
And another friend:
My first wife who died young (44 yrs. old) was a nurse who worked for a doctor here in Bremerton. She often told me of working with patients who came to the office and asked about abortions. This was before Roe vs Wade decision.
A couple of the cases involved those who were concerned because “they already had too many children.” She told them that she was the mother of 3 boys all within 3 years of age. She told them she considered them a blessing and if more were to come she would accept them. As to the difference in age, i.e., 6 to 8 years, between the new baby, this could be a blessing in disguise. The older boys will have somebody to look after and help Mom. By the way, the t here boys all went on to earn doctorates in their chosen field and they did it with minimum assistance from Dad.
This lady needs to talk with somebody outside her family who understands the hidden after effects of abortions. It would be most beneficial if the person were a lay person.
Bob
And a third from another perspective:
I am 11 & 12 years younger than my two sisters. I love them very much and they have been great strength to me after the loss of our mother years ago. Having children spaced apart is a wonderful way for you to enjoy and understand the stages children go through even more, plus it's wonderful for older kids to have a baby brother or sister to help take care of - makes them feel very responsible and important!
Also, I have had two miscarriages, and I always wonder about the people they would have been had they been born... How awful it would be to have that sense and know that you were the one who decided their existence wasn't acceptable!
Some days will be hard, whether you have this baby or not, but please don't put yourself or your 'outside the womb' children through the anguish of knowing that a member of the family is missing. That's just how life is and no one escapes from difficult times. Don't think that killing someone else (your baby) will somehow make it easier. I'm begging you if that is what will work --- please give this baby life!!!