GRAMMAR DETAIL

ものを

if only ... had

Expresses regret or blame over an outcome that could have been avoided if someone had acted differently.

Examples

早く相談すれば解決できたものを、一人で抱え込んでしまった。

If only he had sought advice sooner, the problem could have been solved, but he took it all on by himself.

もっと早く出発すれば間に合ったものを。

If only I had left earlier, I would have made it in time.

すぐに謝れば許してもらえたものを、黙って逃げた。

If only he had apologized right away, he could have been forgiven, but he ran away without saying anything.

Structure: Attach ものを to a favorable outcome that was not realized to express regret or blame that things did not turn out that way.
Basic usage: もっと早く出発すれば間に合ったものを。 regrets not leaving earlier, which would have allowed arrival in time.

Leaving the actual outcome unstated
- Ending with 間に合ったものを leaves the contrasting fact of being late implicit. The actual behavior can also be stated afterward, as in 解決できたものを、一人で抱え込んでしまった.