I'm very much pro-choice, but I feel that the choice clause very much varies with the situation. I feel that getting an abortion (if I were a girl) would be a very hard thing to do. In this scenario, I think that's a matter of just being irresponsible. Yes, it's a woman's body and I feel that the decision is hers and that one should (in most cases) support their choice. But she knew the consequences of having sex and to get an abortion just cause someone broke up with you is not only ridiculous, but a little twisted.
Not only that, but it's bound to have severe psychological and emotional damage on her in the first place, and if she gets a wave of guilt afterwards, it could be really hard for her to cope. She just needs to understand how big that is.
Once again, it's her choice. I just don't think she's doing it for the right reasons.