I can understand that conclusion. I'll do my best to explain my position. How successfully I'll be able to do so is another matter. I believe in evolution and in a very, very old earth. I do not believe that during a six-day period 6000 years ago, God created the earth and dropped two belly-buttonless individuals into a pretty garden and that human life began at that point.
On the other hand, as a theist and as a Mormon, I do believe that God created our universe. I believe He created it is accordance with natural laws. Thus, the entire process started several billion years ago. I believe that human beings (or, more accurately, homo sapiens) first lived on earth (in what is now Africa) somewhere in the neighborhood of 200,000 years ago. This is why I say that from an archeological or mitochondrial perspective, Lucy was the first woman.
While I believe that all of us are probably Lucy's direct descendants, I don't see her as having one thing that the woman Eve had, and that is a spirit that was in God's image. My feelings are that, at some point, at about the time the events in Genesis were said to have transpired, God instilled a spirit in a man (Adam) and a woman (Eve) that did not exist in their ancestor, Lucy, or in any of her descendants up until that time. Eve, unlike Lucy, was of the same species as God himself. The Bible teaches that God is the father of our spirits and that we are not only his creations but his offspring. Lucy, while having a spirit (all living things, according to LDS doctrine, have a spirit), did not have the same kind of spirit as Eve. She was, therefore, one of God's creations but not His offspring.
I should note that this is my personal belief. It does not represent LDS doctrine but it is not contrary to LDS doctrine either. The LDS Church leaves matters of this sort up to personal interpretation. As evidence of this fact, when I first visited the new Natural History Museum of Utah when it first opened a couple of years ago, I noticed that one of the significant benefactors was the LDS Church. The museum is definitely NOT a creationist museum but is as good a natural history museum as you'll find anywhere.