Out of State Guests

I am torn between inviting an out of state guest or not. I have known her family for many years, but I am much closer to her younger sisters than I am with her. The rest of her family lives only a few hours from me, so they will be invited to the wedding (one sister is a bridesmaid). I feel that I should invite her because I am inviting the rest of her family, but I have a strong feeling she will not make the trip due to work and budget restraints (which I am completely understand). I was invited to her wedding reception last year, but her reception was held in her home town a few hours from me so I didn't have any of the travel expenses she would have to attend my wedding. I don't want her to feel left out or forgotten if I don't invite her, but I also don't want her to feel obligated send a gift if she is invited and choses not to make the trip. We would love to have her join us, but I really don't think she will make the trip. Should I send her an invite or not?