Max Evans - Roswell, New Mexico
Max was crushing on Liz hard. Like, really hard. The fact that they didn't get together right away was painful, but it also created a more satisfying build-up.
Jessica Day - New Girl
Even though they had dated in the past, both Nick and Jess decided they were better off as friends. But when none of Jess' other relationships work out, she realizes that she's been in love with Nick the whole time. She keeps her feelings for him a secret and spends a season secretly pining for him, while he's in a serious relationship with Reagan.
Kara Danvers - Supergirl
It may feel like forever ago, but we haven't forgotten that Kara spent the entire first season pining over James. Why didn't they get together again?
Santana Lopez - Glee
Santana was always in love with Brittany, but she was too afraid of coming out and making her feelings known. When she finally did, she was met with acceptance from all of the glee members, and she and Brittany had a double wedding with Kurt and Blaine later on in the series.
Leo Fitz - Agents of S.H.I.E.L.D.
Poor Fitz was always helplessly in love with his best friend, but Jemma had no idea. It actually took them being in a life or death situation for Fitz to finally admit how he feels.
Jim Halpert - The Office
Jim was crushing helplessly on his co-worker since the moment we were introduced to him. The fact that Pam was engaged put a damper on things, but Roy was honestly the worst so we didn't actually care. After his feelings came out, it did take a little for them to make it work, but these two lovebirds got married and had kids.