i totally agree with the reasons you have explained above why sometimes there is need for abortion but different religions have taken strong positions on abortion; they believe that the issue encompasses profound issues of life and death, right and wrong, human relationships and the nature of society, that make it a major religious concern.
People involved in an abortion are usually affected very deeply not just emotionally, but often spiritually, as well. They often turn to their faith for advice and comfort, for explanation of their feelings, and to seek atonement and a way to deal with their feelings of guilt.
Because abortion affects heart as well as mind, and because it involves life and death.