Lovesick.

*credit to @secutegrxnde for the cover*

love·sick /ˈləvˌsik/

adjective

"in love, or missing the person one loves, so much that one is unable to act normally."

The feeling's not mutual.
We have a love-hate relationship. He hates me. I love him.

"You and I redefine being lovesick, lovesick, lovesick. Through it all you could still make my heart skip, heart skip."

-Why Try
Ariana Grande