lovesick

 Longman Dictionary of Contemporary English 5++朗文当代英语 5++LDOCE 5++朗文 5++love·sick /ˈlʌvˌsɪk/ adjective  LOVEspending all your time thinking about someone you love, especially someone who does not love you 单恋的，害相思病的 a lovesick teenager 一个害相思病的少年

Examples from the Corpus

lovesick• From Honk Kong comes a confusing romance about chance encounters between lovesick cops and unusual women.• In her writing she recounts a story about one lovesick cowboy who brandished a pistol at her.• If you're slim, honest and have a good sense of humour then send your photos to this lovesick laddie.• If only she weren't such a lovesick loon.• He knew he was behaving like a lovesick teenager.• You're acting like a lovesick teenager!

love·sick adjectiveChineseSyllable  

all time someone your about Corpus thinking spending

lovesick
love‧sick /ˈlʌvˌsɪk/ adjective
spending all your time thinking about someone you love, especially someone who does not love you:
    a lovesick teenager

love·sickBrE /ˈlʌvsɪk/ 🔊NAmE /ˈlʌvsɪk/ 🔊 adjectiveunable to think clearly or behave in a sensible way because you are in love with sb, especially sb who is not in love with you 害相思病的（尤指单相思的）