i saw this when i was a kid. don't know id its in late 90's or early 2000


this is what i remember:
its a about 2 families living in a duplex; main character are childhood friends; the male lead kept chasing his college crush and then even working at the same company( i think he was an architect), then they eventually became a couple; but soon realizes that the one he truly love was his childhood friend.


hazy memory but its the first time i fell in love with k-drama. i think it appeared on Arirang TV. thank you if someone could help me remember the title.  thank you