Mixed messages about when life begins

When I was young, I knew that life began before birth. I didn't know all the details about fertilization, but I knew very well that the unborn child was human. I knew that women had eggs in their body (I didn't know what sperm were, though), I knew what the uterus was, and I even knew what chromosomes were. I think I knew this because my mom had been pregnant a few times. I even made up a story in which babies were sent from rocket ships from heaven and that's how they got in their mom's womb.
Then I got older, and I got a different message. I was told in church that we entered the world by being born, implying that life began at birth. I was given other messages, even from people who you'd think would be pro-life, that the unborn child wasn't a real person. I now know the problems that such a misconception (forgive the pun) can lead to.
When I found out what abortion was, I strongly supported it in cases of rape, or if the woman's life was in danger, but not for any other reason. I believed that what made abortion wrong was a lot about irresponsibility and not that a human being is being killed. I sort of believed that the fetus was human, but I kind of overlooked that for a while.
Later, I was told that my aunt had a miscarriage and that I wasn't going to have a cousin as soon as I thought. But when my dad told me that, he said something along the lines of "it's not really a baby at this point, but it's a sad thing to go through, so please pray that she'll have peace." I think he was saying that so I wouldn't feel so sad about my cousin's death.
It wasn't until I started reading actual articles about abortion and prenatal development that I really knew that the unborn child was human. I started to feel even more strongly about protecting human life. I felt like it was arbitrary to say that life became important at any other point than when it biologically began.
The other day, abortion came up in a conversation with my grandma. She is against abortion, but her reasoning, like mine was a few years ago, was more about personal responsibility than anything. Later, I said something about it to my dad, and he said "I don't believe life begins at conception... I don't care when life begins." Then I asked him why he was against abortion. He said "because I believe that the unborn thing still has rights." That made me upset, and while crying, I made fun of him by asking if nonliving things, like toilets, should have rights. Then he brought up viability. I told him that viability was overrated. At some point, he said something about how a funeral wasn't held when my mom had a miscarriage. He also said that a strict biological definition of life isn't practical. Well, maybe there's something wrong with society, I thought.
Like I said, it is arbitrary to believe that life becomes important at any other point than when it biologically begins. Is it really that difficult to conceive? (Again, forgive the pun)

--Mary