puppy love

US /ˈpʌp.i ˌlʌv/
UK /ˈpʌp.i ˌlʌv/
"puppy love" picture
1.

romantic love, often intense but usually short-lived, felt by young people

:
Their relationship was just puppy love; it didn't last long.
She thought it was true love, but her parents called it puppy love.