Reacting to Blaine's ex girlfriend

Backstory and what's happening

Lydia is a werewolf and she is a witch. She will be played by Hermione granger and Hayley Marshall and maybe a bit of Kara from supergirl
Backstory: Lydia and Blaine were dating before Kurt came to Dalton because she was the only girl there. Lydia was gonna tell Blaine that she was pregnant but she saw him kissing Kurt she was heartbroken and left. And she had meet Ron and harry and they stayed with her till the baby is there and harry acted like the father figure since they were close and the baby girl liked him more then Ron and since he is the godfather. She became a single mother with the help of harry.  (Her and harry dated but they decided to be friends for anything to be ruin for what they had) Blaine pretends he never dated her for that reason and just told Kurt that he was his first love. (Damn Blaine that's tuff) btw she is Rachel's sister

What's happening now

Kurt always thought he was Blaine's first love and first everything but he saw a photo on Blaine's last post that happened to be right after he and Blaine kissed is this girl and him together close. He tried to ask Blaine about it but he never told Kurt so he talked to the glee club (his family ) about it so let's see what happens when Kurt sees Blaine and Lydia history together will one of them be heartbroken or one will be angry and heartbroken. How will the glee cast react will they be disappointed disgusted or just pity.