It sounds to me like your friend may have unrealistic expectations of you. It's unfair and unrealistic to expect our friends to be interested in every aspect of our lives, and it sounds like your friend is expecting everyone to be interested in and excited about her pregnancy. For example, I work repairing computers and my best friend is a total techno-phobe. She's glad I enjoy what I do and that it's going well for me, but has zero interest in hearing about the improved RAM efficiency in Mavericks. It would be disrespectful of me to prattle on about techy stuff to her and expect her to be interested. Likewise, it's disrespectful of your friend to expect you to be excited about a baby when you have no interest in babies.

Frankly, I think your friend is the one who sounds selfish and self-involved.