Anger and depression are often related. Some theories say that depression is anger turned inward. Anger is unacceptable in some families. If this was the case in your family, you may have learned to submerge your anger and you may be more susceptible to depression now.
Leah suffered from depression which was at least partly related to submerged anger. Another woman might find herself lashing out angrily at those close to her. If she is not usually like this it may be confusing and frightening, but she may have no idea that these angry feelings are associated with her abortion.
You may find that when you are aware of feeling angry, you don't feel depressed. Practice getting angry at someone or something that isn't close at hand, and see if you feel more energized and less depressed. Of course, you can't stomp around all day in a rage, but it helps to really have the physical experience of feeling the depression vanish as you get angry.