Is this fair for a parent to do?

It is not fair that she is disregarding your feelings. But on the other hand put yourself in her shoes. She really likes this guy and as long as he is making her happy and treating her good then it should be okay. But if you really feel like she is just forgetting about you just keep letting her know, or ask her to spend a couple nights out of the week with you. Try to come up with a compromise.