Not invited to bf's graduation

I can't go to my bf's graduation because the school only gives three spots for each graudate and he's going to invite his three close family members. I understand and it would be unfair for me to take that away from his family, but I am definitely feeling some type of way especailly he seems pretty serious about me and even has talked about marriage. What's normal to expect and what would you go about it in this type of situation?