He experienced his first heartbreak.

He was deeply hurt by his first unrequited love.

There is a deep conflict between them.

He suffered a broken heart and stayed in his room all day.

He was heartbroken and stayed in his room all day.

I took my dog to the park.

As time passed, his feelings became stronger.

There is a serious conflict between them.

He stood up and started talking.

He became a respectable businessman.