Help me pls

Hello I'm looking for this one BL manhwa/manga I read a while ago. I apologize if im not very descriptive. I don't remember the main plot exactly but there was this one event where the main couple separated(?) and the uke found someone else to date but that guy only loved him because the uke looked like his girlfriend who was somewhere else (different country maybe) in the end the main couple got together again and the second guy gets back together with his girlfriend. The only character details that I remember is that the uke had black hair and was very depressed to the point of self harm(?) and the second guy tends to smoke a lot which influenced the uke. If you recognize this pls send me the link. Thank you!(⌒▽⌒)