You can follow the ethical principle of always telling the truth, you can also follow the principle of telling white lies whenever that will make the other person feel better.

If you are consistent and the other person can expect you to follow your principles they won't ask you for opinion if the truth will hurt them and you have the policy to always tell the truth.

If you don't have principles and sometimes tell the truth and sometimes tell white lies, it's however much harder for the other person to interact with you to avoid getting hurt.

When driving and there are pedestrians who want to cross the street, you have two valid choices. Stop and let them pass the street before you or continue driving with your speed. When I started taking driving lessons I got the idea of going the middle way of driving slower. That was stupid. It doesn't provide the pedestrians with valid information that they can use to adapt their behavior towards myself.

Hurt feelings often come from people expecting something which doesn't happen. If you follow some codex of ethics and the other person understands which codex of ethics you follow, they won't be in much emotional pain if you act in according with that codex because they can expect you to do so.

it's a matter of preventing people from getting hurt.

The road to hell is paved with good intentions. I don't think that focusing on preventing other people from getting hurt is good for a loving relationship.

In the past I also found it very condescending when other people thought that they should make the decisions about risk getting hurt for me. Give me all the information that I need to make a decision but in the end it's my own decision if I want to risk getting hurt.