Thanks for tackling a tough subject, and for including both your personal experiences and data. I think one challenge with determining the link between practicing a certain religion (while having abortions) is that the term "practicing" can be pretty subjective.
One could just as easily argue that a religious person (especially of a monotheistic faith) who was truly practicing would not lead a life of casual sex followed by abortion. Lifestyle matters. Just because a person self-identifies with a faith group or goes to church on Sundays does not mean that they believe the teachings of their faith, nor are they necessarily "religious."
Generally identifying with a particular faith group is very different from a person actually practicing in their day to day life. You can truly see a person's faith not by how often they go to church, but in the choices they make and how they treat those around them.
Another caveat is whether a person can be practicing if they actively participate in activities that go against their faith. Leaving faith out of it, can a woman call herself a feminist, while actively supporting a man who abuses women? She might self-identify with the feminist movement, but unless she backs it up in action, I'm not sure her self-identificaiton means all that much. What do you think?
Finally, I just wanted to say that my heart goes out to your college roomate. "Casual sex with guys she didn't know enough to remember their names ended in painful procedures and many missed classes." How did this affect her self-esteem? I hope that wherever she is today, she has found happiness and come to understand that the teachings of her faith were not meant to stifle her, but to prevent her from having to suffer through this type of hardship in life. I'm sorry for the ways her parents' influence may have distorted the teachings of the Catholic faith. (I am Catholic myself and I find my faith to be beautiful - though I didn't grow up with overbearing, militant parents, so there's that.)
Anyway, I wrote a whole essay so sorry for the long read! Have a lovely day.